15-111

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Questions and Answers

What is the federal standard for siting meteorological sensors at airports, as mentioned in the content?

AFI 21-103

FCM-S4-1994 (correct)

Chapter 3 and 4 Standard

AN/TMQ-53 Standard

What is the maximum duration for short-term sensor outages before alternative methods are used?

Less than 72 hours (correct)

Less than 96 hours

Less than 24 hours

Less than 48 hours

What happens when weather personnel log out malfunctioning equipment?

Flight safety is compromised

It is not logged out if flight safety warrants otherwise (correct)

It is immediately replaced

Equipment is immediately repaired

What can be used to obtain values during short-term sensor outages?

Laser Range Finders, tactical barometers, hand-held wind readers, or other tactical meteorological equipment Signup and view all the answers

What is a sufficient reason to consider the prevailing visibility the same as at the control tower level?

The presence of a surface-based obscuration, uniformly distributed to heights above the level of the tower. Signup and view all the answers

Why are deficiency reports created for false readings on specific sensors?

To mitigate the risk of false freezing precipitation reports during airfield closure hours Signup and view all the answers

When should a tower visibility remark be included in the next METAR or SPECI?

When the surface prevailing visibility or the control tower visibility is less than 4 SM (6000 m) and the control tower visibility differs from the surface prevailing visibility by a reportable value. Signup and view all the answers

What is the temperature range for evaluating the risk of freezing precipitation?

0 to 3 degrees Celsius Signup and view all the answers

What type of photographs are recommended for visibility reference tools?

High quality color photos taken on a predominantly cloud and obscuration free day. Signup and view all the answers

What happens when the risk of freezing precipitation is low?

Weather personnel coordinate with sensor maintenance personnel to manually disable the freezing precipitation sensor Signup and view all the answers

What should be clearly identified in objects in the visibility reference tool?

The distance and direction from the observation point, as well as whether the markers are day or nighttime aids. Signup and view all the answers

What is the reference for additional information on equipment inventory, status, and utilization reporting?

AFI 21-103 Signup and view all the answers

What is highly recommended for the visibility reference tool?

A hard-copy format. Signup and view all the answers

What can be used to determine marker distances while creating/updating visibility reference tools?

Existing detailed installation maps, military grid reference system maps, map display software/websites, laser range finder equipment, global positioning system, etc. Signup and view all the answers

What are the most suitable daytime markers?

Prominent dark or nearly dark colored objects observed against a light-colored background. Signup and view all the answers

What can WFs/Dets submit to survey the markers through if needed?

A work order to survey the markers through the local Civil Engineering or Army equivalent agency. Signup and view all the answers

What is the unit of measurement used for station pressure and altimeter settings in the United States and at US military organizations overseas?

iHg Signup and view all the answers

What is the range of pressure measurement that FBWOS sensors are capable of?

17.5 to 32.5 iHg Signup and view all the answers

How often are pressure computations made by FBWOS?

Every minute Signup and view all the answers

What is the significance of the four-digit group immediately following the A in the altimeter encoding?

It represents the tens, units, tenths, and hundredths of inches of mercury Signup and view all the answers

What happens to pressure values when they are reported?

They are rounded down to the nearest reportable value Signup and view all the answers

What type of pressure values are considered estimated when the readings are suspect or obtained through any method other than the primary sensor?

All pressure-related values Signup and view all the answers

Under what conditions can the AN/TMQ-53 be used as a back-up without estimating pressure values?

If it has been set-up and properly maintained IAW FCMS4-1994 and the T.O. Signup and view all the answers

What is the primary measurement of atmospheric pressure used in observations?

Station pressure and altimeter setting Signup and view all the answers

What is the primary method for determining Pressure Altitude (PA) and Density Altitude (DA)?

Direct readout from FBWOSs and JET software Signup and view all the answers

What is the difference between the formula used by JET and FBWOS to compute DA?

JET takes into account water vapor, while FBWOS does not Signup and view all the answers

When is it necessary to notify ATC agencies that the reported PA and DA values are estimated?

When the primary pressure sensor is inoperative Signup and view all the answers

What is the purpose of a barometer comparison/calibration program?

To ensure the accuracy of barometers in use Signup and view all the answers

When should comparisons be delayed during barometer calibration?

All of the above Signup and view all the answers

What is the format for reporting rapid pressure changes in the remarks of the observation?

Attachment 3 format Signup and view all the answers

What is the purpose of recording and documenting barometer comparisons?

To maintain a record of barometer comparisons Signup and view all the answers

What is the recommended frequency for establishing a barometer comparison/calibration program?

Monthly Signup and view all the answers

What is the purpose of a METAR/SPECI observation?

To provide surface weather observations and reports Signup and view all the answers

What does the abbreviation 'AO2' stand for?

Remark included in METAR/SPECI observations from FBWOS WFs/Dets without augmentation Signup and view all the answers

What is the purpose of a DAF Form 679?

To request a waiver for a publication compliance item Signup and view all the answers

What does the abbreviation 'CBMAM' stand for?

Cumulonimbus Mammatus Cloud Signup and view all the answers

What is the purpose of a UFC 3-260-01?

To provide airfield and heliport planning and design guidance Signup and view all the answers

What does the abbreviation 'COR' stand for?

Correction to A Previously Disseminated Report Signup and view all the answers

What is the purpose of a JET Form 3818?

To provide surface weather observations and reports Signup and view all the answers

What does the abbreviation 'CIG' stand for?

Ceiling Signup and view all the answers

What should be entered in column 13 of AF Form 3803/JET Form 3813 when an augmented observation is not able to be transmitted longline before the next METAR or SPECI is required?

(FIBI) in parentheses Signup and view all the answers

What should be done when a SPECI is not transmitted longline?

Transmit subsequent SPECI when a significant change occurs Signup and view all the answers

How should reports of a volcanic eruption be disseminated?

Using any reasonable means Signup and view all the answers

What is the purpose of FBWOSs?

To provide official METAR and SPECI observations with augmentation when required Signup and view all the answers

What should be included in a METAR when a later observation containing all elements of a METAR is available for transmission?

(FIBI) in column 13 Signup and view all the answers

How should longline dissemination by another WF/Det be recorded?

In column 13 of AF Form 3803/JET Form 3813 Signup and view all the answers

What is the primary purpose of Chapter 4 of AFMAN15-111?

To provide general procedures for surface weather observations Signup and view all the answers

What type of equipment operates in automated mode at AF and Army controlled airfields?

FBWOSs Signup and view all the answers

What should you do when determining wind direction manually using a compass?

Face into the wind in an unobstructed area Signup and view all the answers

Which of the following can be used to determine wind speed manually if an anemometer is not available?

The Beaufort scale Signup and view all the answers

What is the purpose of the Beaufort scale?

To determine the wind speed Signup and view all the answers

When determining wind speed manually, where should the anemometer be held?

At eye-level Signup and view all the answers

What is the significance of Table 11.2?

Prioritization of reporting layers Signup and view all the answers

What is the lowest priority layer for reporting according to Table 11.2?

Lowest few layer Signup and view all the answers

Which of the following is not a method for determining wind speed?

Using a thermometer Signup and view all the answers

What should you avoid using when determining wind direction?

The movement of clouds Signup and view all the answers

What is the lowest height that FBWOSs can report sky condition from?

100ft Signup and view all the answers

How are heights of layers reported in METAR and SPECI observations?

Using a three-digit value representing hundreds of feet above the surface Signup and view all the answers

What is the sky cover at any level determined by?

The summation principle Signup and view all the answers

What is the minimum amount of sky that a surface-based obscuring phenomenon must cover to be classified as a layer?

1/8th Signup and view all the answers

How are layer heights between 5,000ft and 10,000ft reported?

To the nearest 500ft Signup and view all the answers

What happens when a layer height value falls halfway between two reportable increments?

The lower value is reported Signup and view all the answers

What is the maximum height that FBWOSs can report sky condition up to?

25,000ft Signup and view all the answers

How are clouds and/or obscuring phenomena with bases at approximately the same level classified?

As a single layer Signup and view all the answers

What code figure would be assigned to an atmospheric pressure that is decreasing, then increasing?

5 Signup and view all the answers

What does a code figure of '4' indicate about atmospheric pressure?

It is steady Signup and view all the answers

What code figure would be assigned to an atmospheric pressure that is increasing, then decreasing?

0 Signup and view all the answers

What does a code figure of '7' indicate about atmospheric pressure?

It is decreasing steadily or unsteadily Signup and view all the answers

What code figure would be assigned to an atmospheric pressure that is decreasing, then steady, or decreasing then decreasing more slowly?

6 Signup and view all the answers

What does a code figure of '3' indicate about atmospheric pressure?

It is decreasing, then increasing; or increasing then increasing more rapidly Signup and view all the answers

What is the atmospheric pressure computed for the level of the station elevation?

Station pressure Signup and view all the answers

What code figure would be assigned to an atmospheric pressure that is steady or increasing, then decreasing; or decreasing then decreasing more rapidly?

8 Signup and view all the answers

What code figure would be assigned to an atmospheric pressure that is increasing steadily or unsteadily?

2 Signup and view all the answers

What is the purpose of the altimeter setting?

To indicate the altitude above MSL of an aircraft on the ground Signup and view all the answers

What is the international community's acronym for station pressure?

QFE Signup and view all the answers

What is the report of the theoretical reduction of station pressure to sea level?

Sea-level pressure Signup and view all the answers

What is the purpose of the pressure tendency report?

To indicate the characteristic and amount of pressure change during the 3-hour period Signup and view all the answers

What is the international community's acronym for sea-level pressure?

QFF Signup and view all the answers

What is the frequency of recording station pressure on the observation form?

3-hourly Signup and view all the answers

What is the acronym used to identify an ALSTG in observations at CONUS locations and OCONUS US military locations?

A Signup and view all the answers

What is the location of the primary and discontinuity sensor group for objective elements?

The point of observation used by WF/Det personnel Signup and view all the answers

How are figures and values rounded in this AFMAN?

To the nearest reportable value using the round half up method Signup and view all the answers

How are cloud height and visibility values reported when less than or equal to halfway between two reportable values?

The lower value is reported Signup and view all the answers

How are pressure values rounded when they require rounding to comply with standards of reportable values?

Always rounded down to the next reportable value Signup and view all the answers

How are ALSTGs provided for international aviation purposes and reported in hPa rounded?

Always rounded down to the next whole number Signup and view all the answers

What happens to pressure values when they are reported according to the standards of reportable values?

They are always rounded down Signup and view all the answers

What is the purpose of rounding figures and values to the nearest reportable value?

To comply with standards of reportable values Signup and view all the answers

What is the significance of the method of rounding figures and values in this AFMAN?

It ensures that values are reported accurately and consistently Signup and view all the answers

What is the value of sea-level pressure if the station pressure is 28.8 and the locally designated method is used?

975 Signup and view all the answers

What is the nearest reportable hPa value for a station pressure of 29.75?

1005 Signup and view all the answers

What is the sea-level pressure if the station pressure is 30.4 and the FBWOS is used?

1032 Signup and view all the answers

How should wind direction be disseminated in degrees?

Using three digits, magnetic Signup and view all the answers

What is the reportable hPa value for a station pressure of 29.2?

990 Signup and view all the answers

What should be maintained after disseminating all observations?

A copy of all observations disseminated locally Signup and view all the answers

What is the sea-level pressure if the station pressure is 28.1 and the locally designated method is used?

951 Signup and view all the answers

What is the nearest reportable hPa value for a station pressure of 30.1?

1019 Signup and view all the answers

What should be included when voice is used to disseminate locally during outages of the primary system?

The actual time of observation, time transmitted to the tower, and the initials of the weather technician and receiver Signup and view all the answers

What is the sea-level pressure if the station pressure is 29.9 and the FBWOS is used?

1046 Signup and view all the answers

How should the last observation of the day be identified at limited-duty manual WFs/Dets and gunnery ranges?

By adding the term 'LAST' at the end of the observation Signup and view all the answers

What should be transmitted when it is evident that a weather report will not be completed in time for scheduled transmission?

The contraction 'NIL' at the standard time Signup and view all the answers

What is the reportable hPa value for a station pressure of 29.5?

999 Signup and view all the answers

What is the total sky cover that can be reported according to the summation principle?

8/8ths Signup and view all the answers

What should be maintained for local dissemination of observations by voice relay?

Instructions outlining priorities and procedures Signup and view all the answers

What should be disseminated immediately to local ATC agencies?

All observations, then to other users as established locally Signup and view all the answers

What is the lowest height at which the summation of layers equals broken or greater coverage?

The lowest height at which the summation of layers equals broken or greater coverage Signup and view all the answers

What should be maintained when voice is used to disseminate locally during outages of the primary system?

A record of the actual time of observation, time transmitted to the tower, and the initials of the weather technician and receiver Signup and view all the answers

What is the term used to describe a surface-based phenomenon that completely covers the sky?

Vertical Visibility Signup and view all the answers

What is the coverage of a sky condition reported as 'Scattered'?

3/8ths through 4/8ths Signup and view all the answers

What is the term used to describe a sky condition that is completely covered by clouds or obscuring phenomena?

Overcast Signup and view all the answers

What is the coverage of a sky condition reported as 'Few'?

A trace through 2/8ths Signup and view all the answers

What is the significance of the lowest BKN or greater layer?

It represents the ceiling Signup and view all the answers

What is the term used to describe a sky condition that is completely clear of clouds and obscuring phenomena?

Clear Signup and view all the answers

Under what condition is SLP considered estimated?

When the 12-hour mean temperature is estimated Signup and view all the answers

What is used to determine the pressure tendency when a direct reading is unavailable?

The 3-hour trend of the ALSTGs Signup and view all the answers

What is annotated in column 90 when the 3-hour pressure tendency group is indeterminable?

The reason for not reporting the group Signup and view all the answers

What is used to obtain past pressure information when available?

The FBWOS software Signup and view all the answers

What is determined by taking a direct reading from the FBWOS during the 3-hourly observations?

The pressure tendency Signup and view all the answers

What is used to select the code figure that corresponds to the net change in station pressure?

Table 13.4 Signup and view all the answers

What is considered indeterminable when any portion of the group is impossible to determine?

The 3-hour pressure tendency group Signup and view all the answers

What is used to determine the difference in station pressure from the 3-hour period?

Subtracting the current station pressure from the station pressure from 3 hours ago Signup and view all the answers

What is the primary observation code used by the United States to satisfy requirements for reporting surface meteorological data?

METAR Signup and view all the answers

What type of METAR observations include additional data and are known as “6-hourly observations.”

Those taken at 0000, 0600, 1200, and 1800 UTC Signup and view all the answers

What is the time ascribed to the observation based on when augmenting an FBWOS?

The last observed element to the nearest minute Signup and view all the answers

At what minutes past the hour do WFs/Dets operate with established METAR file times?

55 to 59 minutes Signup and view all the answers

What is the name of the section that contains encoded and/or plain language information that elaborates on data in the body of the METAR observation?

RMK Signup and view all the answers

What is the term used to describe the complete report of wind, visibility, runway visual range (RVR), present weather, sky condition, temperature, dew point, and altimeter setting?

The body of the observation Signup and view all the answers

What is the purpose of a METAR observation?

To report surface meteorological data Signup and view all the answers

What type of observations contain additional information and are known as “3-hourly observations.”

Those taken at 0300, 0900, 1500, and 2100 UTC Signup and view all the answers

What is the purpose of evaluating subjective elements, such as sky condition and visibility, in augmented observations?

To reflect conditions existing at the actual time of observation Signup and view all the answers

Why is it important to observe elements having the greatest rate of change last?

To minimize the impact of changes on observation accuracy Signup and view all the answers

What is the purpose of determining local magnetic declination at each observing location?

To convert wind direction from magnetic to true Signup and view all the answers

How often do most locations experience changes in local magnetic declination?

By several minutes of arc each year Signup and view all the answers

What should weather leadership do regarding local magnetic declination changes?

Monitor FLIPs and revised charts for changes Signup and view all the answers

What is the recommended practice before taking observations at night?

Spend as much time as practicable outside to allow eyes to adjust to lower light conditions Signup and view all the answers

Why is it important to evaluate outdoor elements before indoor elements when conditions are relatively unchanging?

To minimize the impact of changes on observation accuracy Signup and view all the answers

What is the correct order of observing elements when conditions are relatively unchanging?

Outdoor elements, indoor elements, pressure Signup and view all the answers

What is the primary reason for task certified ATC personnel to report changes in tower visibility?

To support the possibility of aircraft diverting in an emergency Signup and view all the answers

What is the minimum visibility required for task certified ATC personnel to take tower visibility observations?

4 SM (6000 m) Signup and view all the answers

What is the purpose of continuous RVR reporting outside controlled airfield hours?

To support aircraft diverting in an emergency Signup and view all the answers

What is the responsibility of weather personnel upon receipt of a tower visibility report?

To evaluate prevailing visibility as soon as practicable Signup and view all the answers

What is the purpose of using tower visibility values as a guide?

To determine surface visibility when the horizon is obstructed Signup and view all the answers

Why do control tower personnel notify the weather technician?

All of the above Signup and view all the answers

What is the significance of leaving runway lights on outside controlled airfield hours?

To support the possibility of aircraft diverting in an emergency Signup and view all the answers

What is the responsibility of task certified ATC personnel?

To take tower visibility observations Signup and view all the answers

How is the sky condition evaluated in a FBWOS?

Based on sensor data gathered during the 30-minute period ending at the actual time of the observation Signup and view all the answers

What is the purpose of a One-Minute Observation (OMO)?

To include all of the basic weather parameters found in the body of the METAR plus specific automated remarks Signup and view all the answers

How are directions encoded in a FBWOS?

In a clockwise order beginning with north Signup and view all the answers

What is the time frame used for evaluating subjective elements such as sky condition, visibility, and present weather in a FBWOS?

A fixed location, time-linear technique Signup and view all the answers

What is included in the encoding of movement of clouds or weather in a FBWOS?

The direction the phenomenon is moving towards Signup and view all the answers

When is the weather technician allowed to manually disseminate the OMO?

Upon arrival at an AOL Signup and view all the answers

Which type of observation uses a fixed location and time-averaging technique for objective elements?

Automated observation Signup and view all the answers

What is the primary purpose of a FBWOS?

To provide automated weather observations Signup and view all the answers

What is the primary purpose of certifying FBWOSs according to FCM-H1?

To conform to the site acceptance procedures and commissioning requirements Signup and view all the answers

What is the primary role of the host-installation AF weather organization at locations with assigned AF weather personnel?

Accomplishing site acceptance and commissioning of FBWOS Signup and view all the answers

What is the primary use of AN/TMQ-53s at AF and Army controlled airfields?

As a backup for fixed meteorological sensors Signup and view all the answers

What is the primary requirement for the use of FBWOSs at locations other than controlled airfields?

Prior approval from the parent MAJCOM Signup and view all the answers

What is the primary function of the FBWOS system in automated mode?

To continually sense, report, and measure atmospheric weather elements Signup and view all the answers

What is the primary responsibility of the Program Manager's Office in the site acceptance and commissioning process?

Coordinating with technical experts and mission owners Signup and view all the answers

What is the primary consideration for siting FBWOS sensor groups at airfields?

Compliance with UFC 3-260-1 Signup and view all the answers

What is the primary purpose of the sponsoring MAJCOM in the site acceptance and commissioning process?

Coordinating with technical experts and mission owners Signup and view all the answers

What is the primary function of the Station Identifier (CCCC) in a METAR or SPECI report?

To represent the airfield identifier according to the ICAO Signup and view all the answers

What is the significance of the 'YYGGggZ' component in a METAR or SPECI report?

It specifies the date and time of the report Signup and view all the answers

Which of the following is NOT a component of a METAR or SPECI report?

Barometric Pressure Signup and view all the answers

What is the purpose of the Remarks Section (RMK) in a METAR or SPECI report?

To include additional information and maintenance data Signup and view all the answers

When is a SPECI report generated?

When SPECI criteria are met during the scheduled time of a routine report Signup and view all the answers

What is the format of the Altimeter setting in a METAR or SPECI report?

APHPHPHPH Signup and view all the answers

What is the purpose of including the 'COR' or 'AUTO' modifier in a METAR or SPECI report?

To indicate the report is corrected or automated Signup and view all the answers

Which of the following is a component of the Body of Report in a METAR or SPECI?

All of the above Signup and view all the answers

What is the primary purpose of a SPECI report?

To report significant weather changes or special conditions Signup and view all the answers

What is the time ascribed to a SPECI report?

The time the SPECI criteria are first met or observed Signup and view all the answers

What is the basis for SPECI criteria?

Published take-off, landing, and circling airfield minima Signup and view all the answers

What is a LOCAL report?

An unscheduled weather observation that does not meet SPECI criteria Signup and view all the answers

When are LOCAL reports taken?

When unit leadership determines there is a requirement in support of local operations Signup and view all the answers

What is the format for encoding LOCAL reports?

METAR format Signup and view all the answers

What is the purpose of supplementing SPECI criteria values?

To ensure consistency with published minima Signup and view all the answers

What is the significance of the time +55 to +59 minutes past the hour in a METAR report?

It is the time the last element of the observation is recorded Signup and view all the answers

What does the abbreviation 'AO1' stand for?

ASOS/AWOS stations without a precipitation discriminator Signup and view all the answers

What is the purpose of a DAFMAN 90-161?

Publishing Processes and Procedures Signup and view all the answers

What is the abbreviation 'ACFT MSHP'?

Aircraft Mishap Signup and view all the answers

What is the purpose of a FAAO JO 7340.2M?

Contractions Signup and view all the answers

What is the abbreviation 'CB'?

Cumulonimbus Cloud Signup and view all the answers

What is the purpose of a UFC 3-260-01?

Airfield and Heliport Planning and Design Signup and view all the answers

What is the abbreviation 'FZRANO'?

Freezing Rain Information Not Available Signup and view all the answers

What is the purpose of a AFMAN 13-204, Volume 3?

Air Traffic Control Signup and view all the answers

Who is the designated commander for Air Force units?

OSS/CC or equivalent Signup and view all the answers

What signifies the weather flight has transformed from the existing system to the newly installed automated system?

IOC Signup and view all the answers

What is the basis for IOC declaration?

Commander's judgment Signup and view all the answers

What is the purpose of the memo submitted to leadership?

To recommend FBWOS certification Signup and view all the answers

What is the significance of FOC declaration?

It indicates the closure of all open write-ups on the AFTO 747 Signup and view all the answers

Who prepares the certification and commissioning documents for submission?

Weather certification official Signup and view all the answers

What is the significance of the weather certification official's satisfaction with system performance?

It is a factor in the commander's IOC decision Signup and view all the answers

What can units do if they have issues with certain portions of the system?

Identify which portions of data they are willing to use and which they will backup/augment Signup and view all the answers

What designation is given to locations with an FBWOS installed?

Automated locations Signup and view all the answers

What is the primary ADS used at the majority of AF Weather operating locations?

Joint Environmental Toolkit (JET) platform Signup and view all the answers

What is the process of declaring initial operating capability (IOC) after all certification and commissioning requirements have been met?

Weather Certification Official Declaration Signup and view all the answers

What is the purpose of the acceptance phase in the FBWOS commissioning process?

To accept the system from the contractor by the acquisition agency Signup and view all the answers

What happens during the installation phase of the FBWOS commissioning process?

Site preparation, hardware installation, checkout, and calibration Signup and view all the answers

What is the result of the FBWOS commissioning process?

All of the above Signup and view all the answers

What is the purpose of the activation phase in the FBWOS commissioning process?

To place the system into pre-operational use Signup and view all the answers

What is the final phase of the FBWOS commissioning process?

Operational capability phase Signup and view all the answers

What is the primary observation code used by the United States to satisfy requirements for reporting surface meteorological data?

METAR Signup and view all the answers

At what times do METAR observations include additional data and are known as '6-hourly observations'?

0000, 0600, 1200, and 1800 UTC Signup and view all the answers

What is the time ascribed to the observation when augmenting an FBWOS?

The time of the last observed element to the nearest minute Signup and view all the answers

What is the purpose of the METAR remarks (RMK) section?

To elaborate on data in the body of the observation Signup and view all the answers

How often do WFs/Dets operate with established METAR file times?

Between 55 to 59 minutes past the hour Signup and view all the answers

What is the purpose of the SPECI report?

To provide a special weather report Signup and view all the answers

What is the time frame for METAR observations taken at 0300, 0900, 1500, and 2100 UTC?

3-hourly observations Signup and view all the answers

What is included in the body of the METAR observation?

Wind, visibility, runway visual range (RVR), present weather, sky condition, temperature, dew point, and altimeter setting Signup and view all the answers

What type of lights should be used as nighttime visibility markers according to AFMAN 13-204v3?

Unfocused lights of moderate intensity Signup and view all the answers

What should WFs/Dets do upon notification of an aircraft mishap?

Immediately encode and disseminate a full element SPECI Signup and view all the answers

What is the purpose of a visibility checkpoint chart or list of visibility markers posted in the control tower?

To assist in determining tower visibility Signup and view all the answers

What should be done when an aircraft is authorized to land using an inactive runway?

Initiate a request for observation data to control aircraft using that runway Signup and view all the answers

What type of equipment is recommended for use in determining visibility markers?

Runway course lights and TV/radio/water tower obstruction lights Signup and view all the answers

What is the purpose of collecting and saving data related to an aircraft mishap?

To follow locally developed guidance and procedures Signup and view all the answers

What is the significance of an aircraft in-flight emergency (IFE) in terms of SPECI requirements?

A SPECI is not required for an in-flight emergency, but weather personnel should be prepared to take a SPECI if the IFE becomes a mishap Signup and view all the answers

What should WFs/Dets do to assist in preparing a chart or markers of suitable objects for determining tower visibility?

Provide whatever assistance is necessary Signup and view all the answers

What is the purpose of time averaging of sensor data in FBWOSs?

To evaluate sky condition over a 30-minute period Signup and view all the answers

What is the difference between an OMO and a METAR/SPECI?

OMO is not normally disseminated Signup and view all the answers

How are directions encoded in a weather observation?

Using a clockwise direction starting from north Signup and view all the answers

What is the purpose of recording and documenting barometer comparisons?

To ensure the accuracy of pressure measurements Signup and view all the answers

What is the primary measurement of atmospheric pressure used in observations?

Station pressure Signup and view all the answers

How are movement entries encoded in a weather observation?

Using the direction of movement towards the phenomenon Signup and view all the answers

What is the purpose of a One-Minute Observation (OMO)?

To generate an observation every minute Signup and view all the answers

What is the significance of the 30-minute period in FBWOSs?

It is the time period for evaluating sky condition Signup and view all the answers

What is the significance of the 'Z' at the end of the date and time group in a METAR report?

It indicates the use of UTC. Signup and view all the answers

What is the purpose of the maintenance indicator '$' in a METAR or SPECI report?

To cue the weather technicians to contact ATC agencies and maintenance personnel and begin back-up procedures. Signup and view all the answers

What is the purpose of the 'COR' modifier in a METAR or SPECI report?

To indicate the report is a correction to a previously disseminated report. Signup and view all the answers

What happens when an element does not occur or cannot be observed in a METAR or SPECI report?

The corresponding group and preceding space are omitted from the report. Signup and view all the answers

When is the 'AUTO' modifier included in a METAR or SPECI report?

When the report is a fully automated report with no human intervention. Signup and view all the answers

What is the purpose of the 'RMK' section in a METAR or SPECI report?

To elaborate on parameters reported in the body of the report. Signup and view all the answers

What happens when a FBWOS cannot provide an element due to sensor failure?

The software automatically places a missing data flag ('M') in the corresponding data field. Signup and view all the answers

When can the 'COR' and 'AUTO' modifiers be used together in a METAR or SPECI report?

Never, they are mutually exclusive. Signup and view all the answers

What is the primary purpose of supplementing observations during controlled airfield hours?

To report weather conditions beyond the capabilities of FBWOS Signup and view all the answers

What is the maximum interval for checking the weather during controlled airfield hours when mandatory supplemental criteria are observed or forecast to occur?

20 minutes Signup and view all the answers

What is the primary responsibility of weather personnel during uncontrolled airfield hours?

To respond to severe weather events in accordance with the Severe Weather Action Plan (SWAP) Signup and view all the answers

What is the precedent for immediate reporting of weather phenomena?

Tornado Signup and view all the answers

What is the criterion for reporting Sandstorms/Dust Storms?

Whenever a local warning is required Signup and view all the answers

What is the purpose of ensuring that all applicable element entries are made in the body of the observation along with accompanying remarks?

To ensure accurate and complete weather reporting Signup and view all the answers

What is the requirement for reporting a Tower Visibility remark?

Only during controlled airfield hours Signup and view all the answers

What is the purpose of having a Severe Weather Action Plan (SWAP) in place?

To respond to severe weather events during uncontrolled airfield hours Signup and view all the answers

What is the minimum difference in speed required to report supplemental wind data for an inactive/parallel runway?

6 kt Signup and view all the answers

Where can supplemental RVR data for an inactive runway be reported?

In the remarks section of an observation Signup and view all the answers

Why can WFs/Dets report significant or unusual variations in the sky condition in the remarks section of the observation?

Because local PIREPs report variations in the sky condition Signup and view all the answers

What is the minimum difference in temperature required to report supplemental temperature data for an inactive/parallel runway?

One reportable value Signup and view all the answers

What happens when wind data is obtained as back-up from an inactive sensor?

It is reported as estimated Signup and view all the answers

What is the purpose of using inactive/parallel runway equipment as back-up?

To obtain objective elements when the active weather sensor is questionable Signup and view all the answers

What is an example of how supplemental cloud height data can be reported in the remarks section of an observation?

CLD LYR AT 400FT ON APCH RWY 23 Signup and view all the answers

What is the format for reporting supplemental temperature data for an inactive/parallel runway?

TEMPERATURE 23C RWY11 Signup and view all the answers

When is a tower visibility remark included in the next METAR or SPECI?

When the observed tower prevailing visibility decreases to less than 4 SM or increases to or exceeds 4 SM Signup and view all the answers

What is the purpose of continuous RVR reporting outside controlled airfield hours?

To support emergency diversions into the location Signup and view all the answers

What is the primary reason for task certified ATC personnel to take tower visibility observations?

To report changes in tower visibility when it is less than 4 SM and differs from the prevailing visibility by at least one reportable value Signup and view all the answers

What should weather personnel do upon receipt of a tower visibility report that differs from the latest reported surface visibility?

Evaluate the prevailing visibility as soon as practicable Signup and view all the answers

Why do task certified ATC personnel notify the weather technician when the observed tower prevailing visibility decreases to less than 4 SM or increases to or exceeds 4 SM?

To report changes in tower visibility Signup and view all the answers

What is the purpose of relaying PIREPs as soon as practical within ATC established duty priorities?

To relay pilot reports of weather conditions as soon as practical Signup and view all the answers

What is the significance of tower visibility observations taken by task certified ATC personnel?

To report changes in tower visibility when it is less than 4 SM and differs from the prevailing visibility by at least one reportable value Signup and view all the answers

What is the primary purpose of weather personnel evaluating prevailing visibility upon receipt of a tower visibility report?

To determine the surface visibility when portions of the horizon are obstructed Signup and view all the answers

Atmospheric pressure is now higher than 3 hours ago. What is the code figure for pressure characterization?

0 Signup and view all the answers

What is the code figure for atmospheric pressure that is decreasing, then increasing?

5 Signup and view all the answers

Atmospheric pressure is now the same as 3 hours ago. What is the code figure for pressure characterization?

4 Signup and view all the answers

What is the code figure for atmospheric pressure that is increasing steadily or unsteadily?

2 Signup and view all the answers

Atmospheric pressure is now lower than 3 hours ago. What is the code figure for pressure characterization?

7 Signup and view all the answers

What is the code figure for atmospheric pressure that is decreasing, then steady; or decreasing then decreasing more slowly?

6 Signup and view all the answers

What is the code figure for atmospheric pressure that is increasing, then decreasing?

0 Signup and view all the answers

What is the code figure for atmospheric pressure that is steady or increasing, then decreasing; or decreasing then decreasing more rapidly?

8 Signup and view all the answers

What does the abbreviation 'ASOS' stand for?

Automated Surface Observing System Signup and view all the answers

What is the purpose of a DAFMAN 15-129?

Air and Space Weather Operations Signup and view all the answers

What is the unit of measurement used for station pressure and altimeter settings in the United States and at US military organizations overseas?

inches of Mercury Signup and view all the answers

What is the purpose of a UFC 3-260-01?

Airfield and Heliport Planning and Design Signup and view all the answers

What does the abbreviation 'AO1' stand for?

ASOS/AWOS stations without a precipitation discriminator Signup and view all the answers

What is the purpose of a AF Form 3622?

Air Traffic Control/Weather Certification and Rating Record Signup and view all the answers

What is the purpose of a FAAO JO 7350.9EE?

Location Identifiers Signup and view all the answers

What does the abbreviation 'OFCM' stand for?

Office of the Federal Coordinator for Meteorology Signup and view all the answers

What is the minimum number of comparisons required to determine a mean correction for a deployable barometer?

Four Signup and view all the answers

When can a deployable barometer be used without being compared to a standard barometer?

Never, it must always be compared to a standard barometer Signup and view all the answers

What happens if the corrected reading of a deployable barometer differs from the standard barometer by more than 0.01 inHg (0.34 hPa)?

The steps are re-accomplished Signup and view all the answers

What is the minimum time interval between comparisons when determining a mean correction for a deployable barometer?

15 minutes Signup and view all the answers

What is used as a standard barometer for handheld barometers?

Local observing system Signup and view all the answers

What happens if the corrected reading of a deployable barometer exceeds 0.03 inHg (1.01 hPa) from the standard barometer?

The barometer is turned in to depot maintenance Signup and view all the answers

At what locations can a deployable barometer be compared to any available calibrated pressure instrument?

At locations without a standard barometer Signup and view all the answers

How often should a deployable barometer be compared to a standard barometer?

Before deployment and after redeployment Signup and view all the answers

During controlled airfield hours, what is the maximum time interval for checking the weather?

20 minutes Signup and view all the answers

What is the primary reason for immediately reporting tornadic activity?

To take precedence over all other phenomena Signup and view all the answers

What is the threshold for task certified ATC personnel to take tower visibility observations?

4 SM (6000 m) Signup and view all the answers

What is the condition under which a tower visibility remark is required?

During controlled airfield hours Signup and view all the answers

What happens when the observed tower prevailing visibility decreases to less than 4 SM (6000 m) or increases to or exceeds 4 SM (6000 m)?

Task certified ATC personnel notify the weather technician. Signup and view all the answers

What is the purpose of a SWAP?

To respond to severe weather threats Signup and view all the answers

Why are RVR system runway lights required to be left on outside controlled airfield hours?

To assist with aircraft navigation during emergencies. Signup and view all the answers

When is it necessary to report Sandstorms/Dust Storms?

When a local warning for the conditions is required Signup and view all the answers

What is the purpose of weather personnel evaluating prevailing visibility upon receipt of a tower visibility report?

To use the tower visibility value as a guide. Signup and view all the answers

What is the purpose of mandatory supplementation?

To manually add observed weather conditions beyond the capabilities of the FBWOS Signup and view all the answers

What is required during uncontrolled airfield hours?

Responding to severe weather threats Signup and view all the answers

What is the significance of reporting changes in tower visibility when it is less than 4 SM (6000 m) and differs from the prevailing visibility by at least one reportable value?

To fulfill ATC directives. Signup and view all the answers

What is the primary purpose of weather personnel supplementing observations?

To manually add observed weather conditions beyond the capabilities of the FBWOS to detect and/or report to an observation Signup and view all the answers

What is the responsibility of task certified ATC personnel regarding PIREPs?

To relay PIREPs as soon as practical within ATC established duty priorities. Signup and view all the answers

What is the purpose of the cooperative weather watch?

To ensure continuous RVR reporting outside controlled airfield hours. Signup and view all the answers

What is the significance of WFs/Dets notifying airfield leadership when continuous RVR reporting is needed outside controlled airfield hours?

To ensure the RVR system runway lights are left on. Signup and view all the answers

What is the purpose of computing station pressure?

To derive all other pressure reports Signup and view all the answers

What is the acronym used by the international community for altimeter setting?

QNH Signup and view all the answers

What is the purpose of sea-level pressure reports?

To report the theoretical reduction of station pressure to sea level Signup and view all the answers

What is included in the 3-hourly observations?

Pressure tendency reports Signup and view all the answers

What is the acronym used by the international community for sea-level pressure?

QFF Signup and view all the answers

What is the purpose of pressure tendency reports?

To indicate the characteristic and amount of pressure change Signup and view all the answers

What is recorded at 3-hourly intervals on the observation form?

Station pressure reports Signup and view all the answers

What is used to identify an ALSTG in observations at CONUS locations and OCONUS US military locations?

The letter 'A' Signup and view all the answers

What is the purpose of the weather certification official's memo?

To recommend commissioning of the FBWOS Signup and view all the answers

What is the purpose of task-certifying ATC personnel?

To evaluate tower visibility values Signup and view all the answers

What is attached to the commissioning document?

The new station information file Signup and view all the answers

Where is the copy of the document package retained?

In the flight's permanent historical file Signup and view all the answers

What is the significance of the accuracy of time in weather observations?

It is only important for aviation safety investigations Signup and view all the answers

What is used to verify the Base/Post network time?

A Naval Observatory clock Signup and view all the answers

How often are time checks annotated in Column 90 of AF Form 3803/JET Form 3813?

At each observation Signup and view all the answers

Where is the station information file sent to?

14 WS/DOD and 2 SYOS/SYSD Signup and view all the answers

What is the primary consideration when determining whether to report rapid pressure changes?

Rate of pressure change Signup and view all the answers

What is the purpose of providing DA values obtained directly from the ADS and TMQ-53 sensor displays?

To support local ATC agencies Signup and view all the answers

What is the typical frequency of pressure computations made by FBWOS?

Automatically Signup and view all the answers

What is the primary purpose of comparing and calibrating barometers?

To ensure the accuracy of pressure measurements Signup and view all the answers

What is the condition under which comparisons should be delayed during barometer calibration?

During all of the above Signup and view all the answers

What is the primary method of determining Pressure Altitude (PA) and Density Altitude (DA)?

Using the FBWOS or JET software Signup and view all the answers

What is the significance of the four-digit group immediately following the A in the altimeter encoding?

It represents the station pressure in hectopascals Signup and view all the answers

When is it necessary to notify ATC agencies that the reported PA and DA values are estimated?

When the primary pressure sensor is inoperative Signup and view all the answers

What is the purpose of establishing procedures locally in an order of priority during ADS outages?

To ensure timely dissemination of observations to ATC Signup and view all the answers

What should be done with observations during ADS outages or if ADS is not available?

Disseminate to ATC first Signup and view all the answers

What is the primary function of the FBWOS system in automated mode?

To sense and report weather elements Signup and view all the answers

What is the correct order of dissemination during ADS outages or if ADS is not available?

ATC first, then local customers and longline transmission Signup and view all the answers

At which type of locations are AN/TMQ-53s used as a backup?

Tactical airfields Signup and view all the answers

Why should local dissemination procedures be coordinated with local customers?

To agree on code form, format, and content Signup and view all the answers

Who is responsible for site acceptance and commissioning at locations with assigned AF weather personnel?

The host-installation AF weather organization Signup and view all the answers

What should be included in local weather documentation?

Code form, format, and content Signup and view all the answers

What is required for the use of FBWOS at locations other than controlled airfields?

Approval from the parent MAJCOM Signup and view all the answers

What is the purpose of documenting local weather documentation?

To record local dissemination procedures and code form, format, and content Signup and view all the answers

What is the federal standard for siting FBWOS sensor groups?

UFC 3-260-1 Signup and view all the answers

What is the correct order of actions during ADS outages or if ADS is not available?

Disseminate to ATC, establish procedures locally, and then document in local weather documentation Signup and view all the answers

Who coordinates site acceptance and commissioning at locations with a DAF-owned FBWOS but no DAF weather personnel?

The sponsoring MAJCOM, Lead Command, and the Program Managers Office Signup and view all the answers

Why is it important to establish procedures locally during ADS outages or if ADS is not available?

To ensure timely dissemination of observations Signup and view all the answers

What is the purpose of FBWOSs procured for operation on AF and Army locations?

To conform to the station certification requirements Signup and view all the answers

What is the significance of siting FBWOS sensor groups in accordance with the federal standard?

To ensure the accuracy of weather reports Signup and view all the answers

During periods when the ADS is unavailable, which system should be used to disseminate observations longline?

AF Weather-Web Service (AFW-WEBS) Signup and view all the answers

When should corrections (COR) to transmitted data be disseminated?

Immediately after the error is detected Signup and view all the answers

What is the correct format for reporting Pressure Altitude (PA) or Density Altitude (DA) in an observation?

PA +130 or DA +3680, following the last element or remark Signup and view all the answers

What does the abbreviation 'ALSTG' stand for?

Altimeter Setting Signup and view all the answers

What is the purpose of a METAR/SPECI observation?

To provide weather information for flight planning Signup and view all the answers

What should be included in a transmitted correction (COR) observation?

The entire corrected observation Signup and view all the answers

What is the purpose of disseminating Pressure Altitude (PA) and Density Altitude (DA)?

To provide essential information for aircraft operations Signup and view all the answers

What is the unit of measurement used for station pressure and altimeter settings in the United States and at US military organizations overseas?

Inches of Mercury Signup and view all the answers

What should be used to determine the date and time in a transmitted correction (COR) observation?

The original date and time of the observation Signup and view all the answers

What does the abbreviation 'FZRANO' stand for?

Freezing Rain Information Not Available Signup and view all the answers

What is the purpose of a UFC 3-260-01?

Airfield and Heliport Planning and Design Signup and view all the answers

What is the primary local and longline dissemination system used by most WFs/Dets?

ADS Signup and view all the answers

How should Pressure Altitude (PA) or Density Altitude (DA) be disseminated when required?

Following the last element or remark in the observation Signup and view all the answers

What does the abbreviation 'AO1' stand for?

ASOS/AWOS stations without a precipitation discriminator Signup and view all the answers

What is the purpose of a DAF Form 679?

Department of the Air Force Publication Compliance Item Waiver Request/Approval Signup and view all the answers

What does the abbreviation 'CCSL' stand for?

Cirrocumulus Standing Lenticular Cloud Signup and view all the answers

What is the primary reason for considering the prevailing visibility the same as at the control tower level?

The control tower visibility is uniformly distributed to heights above the level of the tower. Signup and view all the answers

When should a tower visibility remark be included in the next METAR or SPECI?

When the control tower visibility differs from the surface prevailing visibility by a reportable value. Signup and view all the answers

What is the recommended format for visibility reference tools?

Hard-copy format with photographs and maps. Signup and view all the answers

What is the purpose of developing map-type visibility charts?

To augment the photographic visibility markers. Signup and view all the answers

What should be used to determine marker distances while creating/updating visibility reference tools?

All of the above. Signup and view all the answers

What are the most suitable daytime markers?

Prominent dark or nearly dark colored objects observed against a light-colored background. Signup and view all the answers

What should be clearly identified in objects in the visibility reference tool?

All of the above. Signup and view all the answers

What can WFs/Dets submit to survey the markers through if needed?

A work order to the local Civil Engineering or Army equivalent agency. Signup and view all the answers

When using an object as a nighttime visibility marker, what type of light should be used?

Unfocused light of moderate intensity Signup and view all the answers

What is required to be maintained in control towers according to AFMAN 13-204v3?

A list of visibility markers Signup and view all the answers

What action should WFs/Dets take upon notification of an aircraft mishap?

Immediately encode and disseminate a full element SPECI Signup and view all the answers

What happens when ATC authorizes an aircraft to land using an inactive runway?

The current observation is not affected and the active runway remains the same Signup and view all the answers

What should weather personnel do when augmentation is no longer required?

Reconfigure their ADS to disseminate in the automated mode Signup and view all the answers

What should be used to determine the elements of an observation when augmenting?

Manual observing methods Signup and view all the answers

What should WFs/Dets do to help prepare a chart or markers of suitable objects for determining tower visibility?

Provide assistance to control towers upon request Signup and view all the answers

What type of lights should not be used as nighttime visibility markers?

Focused lights of high intensity Signup and view all the answers

Why should weather personnel have a view of the airfield complex when augmenting?

To maintain situational awareness of the current conditions Signup and view all the answers

What is the purpose of documenting augmented observations?

To provide a record of the augmented observation Signup and view all the answers

What should WFs/Dets collect and save in accordance with DAFMAN 15-129 upon notification of an aircraft mishap?

Data related to the mishap Signup and view all the answers

What happens to the 'AUTO' report modifier when weather personnel select the augmented or manual mode?

It is removed from the observation Signup and view all the answers

What is the purpose of providing supplemental data when an aircraft is authorized to land using an inactive runway?

To provide additional data for air traffic control Signup and view all the answers

What is not used to back-up a faulty RVR reading?

Inactive/parallel runway equipment Signup and view all the answers

What is the purpose of augmenting surface weather observations produced by an FBWOS?

To edit or add additional data to an observation generated by an FBWOS Signup and view all the answers

What is required to augment surface weather observations produced by an FBWOS?

View of the airfield complex and situational awareness of the current conditions Signup and view all the answers

When does the Control Tower observe prevailing visibility?

When the prevailing visibility at the point of observation or at the tower level is less than 4 SM (6000 m) Signup and view all the answers

What should weather personnel do when they receive a tower visibility report that differs from the latest reported surface visibility?

Evaluate prevailing visibility as soon as practicable Signup and view all the answers

What is the purpose of leaving the runway lights on during controlled airfield hours?

To support the possibility of an aircraft diverting in an emergency Signup and view all the answers

What is the criterion for reporting wind direction as variable?

Wind direction is not meeting specific criteria Signup and view all the answers

What is the time period used to determine wind gusts?

10-minute period Signup and view all the answers

When should task certified ATC personnel take tower visibility observations?

When the prevailing visibility at the point of observation or at the tower level is less than 4 SM (6000 m) Signup and view all the answers

What do task certified ATC personnel notify the weather technician of?

When the prevailing visibility decreases to less than 4 SM (6000 m) or increases to or exceeds 4 SM (6000 m) Signup and view all the answers

What is the criteria for reporting peak wind speed in the remarks of a METAR?

When the speed is greater than 25 knots Signup and view all the answers

What is the purpose of the cooperative weather watch?

To support continuous RVR reporting outside controlled airfield hours Signup and view all the answers

What is a wind shift?

A change in wind direction by at least 45 degrees Signup and view all the answers

What should weather personnel use as a guide in determining the surface visibility?

The prevailing visibility at the tower level Signup and view all the answers

What determines the predominant wind direction, speed, gusts, and shifts?

Primary active wind sensor Signup and view all the answers

What is the unit of measurement used to report wind speed?

Whole knots Signup and view all the answers

What should task certified ATC personnel relay to other parties as soon as practical?

PIREPs Signup and view all the answers

What is the purpose of reporting peak wind speed?

To report the highest instantaneous wind speed Signup and view all the answers

What determines the peak wind data?

All available runway sensors Signup and view all the answers

What is the equivalent pressure in hectopascals for a Code figure of 030.090 in inches of mercury?

3.0 Signup and view all the answers

What is the Code figure in inches of mercury equivalent to a pressure of 15.2 hectopascals?

152.450 Signup and view all the answers

What is the pressure in hectopascals corresponding to a Code figure of 100.295 in inches of mercury?

10.0 Signup and view all the answers

What is the Code figure in inches of mercury equivalent to a pressure of 8.5 hectopascals?

085.250 Signup and view all the answers

What is the pressure in hectopascals corresponding to a Code figure of 050.150 in inches of mercury?

5.1 Signup and view all the answers

What is the Code figure in inches of mercury equivalent to a pressure of 12.2 hectopascals?

122.360 Signup and view all the answers

What is the pressure in hectopascals corresponding to a Code figure of 060.180 in inches of mercury?

6.1 Signup and view all the answers

What is the Code figure in inches of mercury equivalent to a pressure of 19.5 hectopascals?

195.575 Signup and view all the answers

During periods when the ADS is unavailable, what should be used to disseminate observations longline?

All of the above Signup and view all the answers

How should corrections (COR) to transmitted data be disseminated?

In the same manner as the original observation Signup and view all the answers

What is disseminated locally?

Pressure altitude (PA) and density altitude (DA) Signup and view all the answers

When should runway condition remarks be reported?

Last in the observation Signup and view all the answers

What is included in transmitted corrections?

The entire corrected observation Signup and view all the answers

What is the purpose of Attachment 3 (T-0)?

To explain the process of correcting transmitted data Signup and view all the answers

What determines the date and time in the COR'd observation?

The time of the original observation Signup and view all the answers

What is an example of an augmented longline dissemination of METARs/SPECIs?

Figure 3.2 Signup and view all the answers

What is the primary purpose of computing station pressure?

To derive all other pressure reports Signup and view all the answers

What is the acronym used by the international community to refer to altimeter setting?

QNH Signup and view all the answers

What is the report of the theoretical reduction of station pressure to sea level?

Sea-level Pressure (SLP) Signup and view all the answers

What is included on the 3-hourly observations to indicate the characteristic and amount of pressure change during the 3-hour period?

Pressure Tendency Signup and view all the answers

What is the acronym used by the international community to refer to Sea-level Pressure (SLP)?

QFF Signup and view all the answers

How often are station pressure values recorded?

At 3-hourly intervals Signup and view all the answers

What is the purpose of computing altimeter setting?

To determine the altitude above MSL of an aircraft on the ground Signup and view all the answers

What is the letter used to identify an altimeter setting in observations at CONUS locations and OCONUS US military locations?

A Signup and view all the answers

What is the estimated cloud base height in feet when the surface dewpoint depression is 1.5°C?

600 Signup and view all the answers

What is the estimated cloud base height in feet when the surface dewpoint depression is 12.5°C?

5,000 Signup and view all the answers

What is the unit of measurement used for reporting pressure values in the United States and at US military organizations overseas?

inches of mercury (iHg) Signup and view all the answers

What is the significance of the letter 'A' in the altimeter encoding?

It is the international indicator for altimeter in inches of mercury Signup and view all the answers

What is the primary measurement of atmospheric pressure used in observations?

Barometer Signup and view all the answers

What is the purpose of a barometer comparison/calibration program?

To evaluate the performance of barometers Signup and view all the answers

What is the format for reporting rapid pressure changes in the remarks of the observation?

PRESRR Signup and view all the answers

What is the purpose of recording and documenting barometer comparisons?

To evaluate the performance of the barometer Signup and view all the answers

What is the equivalent value in hectopascals for a pressure of 038.145 inches of mercury?

12.9 Signup and view all the answers

What is the equivalent value in inches of mercury for a pressure of 159.470 hectopascals?

7.80 Signup and view all the answers

What is the pressure in inches of mercury corresponding to 14.1 hectopascals?

041.120 Signup and view all the answers

What is the equivalent value in hectopascals for a pressure of 186.550 inches of mercury?

18.5 Signup and view all the answers

What is the pressure in hectopascals corresponding to 3.9 inches of mercury?

39.110 Signup and view all the answers

What is the equivalent value in inches of mercury for a pressure of 20.0 hectopascals?

069.200 Signup and view all the answers

What is the pressure in hectopascals corresponding to 151.445 inches of mercury?

15.1 Signup and view all the answers

What is the equivalent value in inches of mercury for a pressure of 12.5 hectopascals?

034.125 Signup and view all the answers

What does the abbreviation 'AFMAN' stand for?

Air Force Manual Signup and view all the answers

What is the purpose of a DAF Form 847?

Recommendation for Change of Publication Signup and view all the answers

What does the abbreviation 'AOL' stand for?

Alternate Operating Location Signup and view all the answers

What is the purpose of a Qualification Training Package Observing, Trainer’s Guide?

To provide trainers with guidance on observing and reporting weather Signup and view all the answers

What does the abbreviation 'AO1' stand for?

ASOS/AWOS stations without a precipitation discriminator Signup and view all the answers

What is the purpose of a Federal Meteorological Handbook No. 1 (FCM-H1)?

Surface Weather Observations and Reports Signup and view all the answers

What does the abbreviation 'APRNT' stand for?

Apparent Signup and view all the answers

What is the purpose of a WMO-No. 306, Manual on Codes?

To provide standards for weather coding Signup and view all the answers

What is the purpose of the 'RMK' section in a METAR or SPECI report?

To provide automated, manual and plain language information Signup and view all the answers

What is the format of the station identifier in a METAR or SPECI report?

Four alphanumeric characters Signup and view all the answers

What is the purpose of the 'METAR' or 'SPECI' type report?

To provide weather information to aircraft operators and air traffic control Signup and view all the answers

What is included in the 'Date and Time of Report' section of a METAR or SPECI report?

Both the date and time Signup and view all the answers

Who is responsible for preparing a memo recommending commissioning of the FBWOS?

The weather certification official Signup and view all the answers

What is the purpose of task certifying ATC personnel?

To evaluate tower visibility values Signup and view all the answers

What is the purpose of the 'CLR' indicator in the 'Sky Condition' section of a METAR or SPECI report?

To indicate clear sky conditions Signup and view all the answers

Where should the signed commissioning document and attachments be mailed?

14 WS/DOD and 2 SYOS/SYSD Signup and view all the answers

What is the unit of measurement used for visibility in a METAR or SPECI report?

Statute miles Signup and view all the answers

What is the standard clock used for weather observations?

A standalone clock zeroed with the US Naval Observatory time Signup and view all the answers

What is the purpose of the 'T'T''/T'dT'd' section in a METAR or SPECI report?

To provide temperature and dew point information Signup and view all the answers

Where should the station information file be emailed or mailed to?

14WS/WXD, 151 Patton Avenue, Asheville, NC 28801-5002 Signup and view all the answers

What is the purpose of the 'AO2' abbreviation in a METAR or SPECI report?

To indicate automated observation Signup and view all the answers

What is annotated in Column 90 on AF Form 3803/JET Form 3813?

Time checks Signup and view all the answers

Who logs DAF ATC task certification on AF Form 3622?

Weather personnel Signup and view all the answers

What is the purpose of position qualification requirements for weather personnel?

To ensure weather personnel are trained, task certified, and position qualified Signup and view all the answers

What is the encoded format for wind direction in an unobstructed area?

dddff(f)KT Signup and view all the answers

What is the unit of measurement used for wind speed reporting?

Knots Signup and view all the answers

What happens when weather personnel log out the freezing precipitation sensor?

The duration of each event can be tracked Signup and view all the answers

What is the purpose of measuring wind in an unobstructed area?

To minimize inconsistencies caused by local obstructions Signup and view all the answers

How is wind speed encoded when it exceeds 100 knots?

Using the hundreds digit Signup and view all the answers

What is the format for reporting wind direction and speed in a METAR?

dddff(f)KT Signup and view all the answers

What happens to the system's freezing precipitation sensor when weather leadership is involved?

Personnel are physically present to back-up the system Signup and view all the answers

When are CB and TCU appended to the cloud layer report?

When observed within 10nm Signup and view all the answers

How are total layer coverage and total sky cover determined?

By mentally dividing the sky into halves, quarters, and/or eighths Signup and view all the answers

What is the significance of the base appearing horizontal and at a different height than the parent cloud?

It indicates a separate layer Signup and view all the answers

What is the purpose of column 13 remarks?

To report significant cloud features Signup and view all the answers

What happens when evaluating interconnected layers formed by the horizontal extension of cumulus?

The entire cloud is regarded as a single layer Signup and view all the answers

What is considered when determining total layer and sky cover amount?

The bases and sides of clouds or obscuring phenomenon Signup and view all the answers

What should be avoided when evaluating cloud coverage?

Reducing coverage estimation to compensate for the packing effect Signup and view all the answers

What is the purpose of Figure 11.1?

To show how to determine total layer and sky cover Signup and view all the answers

To convert magnetic direction to true direction, what operation should be performed?

Add easterly declination to magnetic direction and subtract westerly declination Signup and view all the answers

What is the definition of an unofficial weather report?

A report of one or more weather elements from an individual who is not task-certified Signup and view all the answers

What is the purpose of reporting unofficial weather reports from credible sources within 10 SM?

To provide additional information to local aviation and public safety Signup and view all the answers

What is the definition of the 'point of observation' for meteorological observations?

The designated spot where the elements of an observation are viewed and/or sensed Signup and view all the answers

What happens when the primary sensor group or discontinuity sensor group is moved?

The updated latitude, longitude, and elevation are provided in the station information file Signup and view all the answers

What is the purpose of documenting the point of observation in the weather support plan?

To document exceptions to the 5 SM rule Signup and view all the answers

What type of observations are made when the point of observation is the location of the primary sensor group and the discontinuity sensor group?

Automated observations Signup and view all the answers

When is an unofficial weather report disseminated longline and locally?

During augmentation of an FBWOS Signup and view all the answers

What is the maximum time interval at which WFs/Dets will disseminate an ALSTG LOCAL observation when there has been a change of 0.01 inches of mercury or more since the last disseminated ALSTG value?

35 minutes Signup and view all the answers

What are the two major sections of a METAR/SPECI report?

Body and Remarks Signup and view all the answers

What is the purpose of the Station Identifier (CCCC) in a METAR or SPECI report?

To identify the observing location Signup and view all the answers

What is the format of the Date and Time of Report in a METAR or SPECI report?

YYGGggZ Signup and view all the answers

What indicates a required space between the groups in the METAR/SPECI code format?

_ Signup and view all the answers

What fulfills the requirement for disseminating an ALSTG LOCAL observation at an interval not to exceed 35 minutes?

A METAR or SPECI taken within the established time interval Signup and view all the answers

What is the purpose of the Report Modifier (COR or AUTO) in a METAR or SPECI report?

To indicate whether the report is corrected or automated Signup and view all the answers

What determines the actual content of a METAR/SPECI report?

The observation program at the individual observing organization Signup and view all the answers

What is the purpose of the Remarks Section of a METAR or SPECI report?

To provide additional information about the report Signup and view all the answers

What is the significance of the SPECI report type?

It is a special report that meets specific criteria Signup and view all the answers

What is the purpose of documenting the contents of LOCALs in base/host unit support plans, local weather support agreements, or standard operating procedures?

To establish the contents of LOCALs for agencies other than ATC Signup and view all the answers

What is the unit of measurement used for altimeter settings in the United States and at US military organizations overseas?

Inches of mercury Signup and view all the answers

What is the purpose of the Altimeter section of a METAR or SPECI report?

To specify the altimeter setting Signup and view all the answers

What is the purpose of the Present Weather section of a METAR or SPECI report?

To indicate the present weather conditions Signup and view all the answers

What is the significance of the four-digit group immediately following the A in the altimeter encoding?

It indicates the altimeter setting Signup and view all the answers

What is the purpose of the Sky Condition section of a METAR or SPECI report?

To indicate the sky condition Signup and view all the answers

What is the function of the 'M' and '$' characters in a METAR or SPECI report?

To cue weather technicians to contact ATC agencies and maintenance personnel Signup and view all the answers

What is the purpose of the Remarks (RMK) section in a METAR or SPECI report?

To provide additional information about the weather conditions Signup and view all the answers

What is the significance of the 'Z' at the end of the date and time group in a METAR or SPECI report?

It indicates the use of UTC time Signup and view all the answers

What happens when a corrected METAR or SPECI report is transmitted?

The corrected report uses the same time as the original report Signup and view all the answers

What is the purpose of the AUTO modifier in a METAR or SPECI report?

To identify the report as fully automated with no human intervention Signup and view all the answers

What happens when an element is missing or cannot be observed in a METAR or SPECI report?

The corresponding group and preceding space are omitted from the report Signup and view all the answers

What is the significance of the COR modifier in a METAR or SPECI report?

It identifies the report as a correction to a previously disseminated report Signup and view all the answers

What happens when a weather technician signs off the automated dissemination system (ADS)?

The report is transmitted with an AUTO modifier Signup and view all the answers

What is the primary purpose of certifying FBWOSs in accordance with FCM-H1?

To achieve operational evaluation and fielding decision Signup and view all the answers

Who is responsible for site acceptance and commissioning at locations with assigned AF weather personnel?

The host-installation AF weather organization Signup and view all the answers

What is the primary limitation of using AN/TMQ-53s?

They cannot be used as standalone weather sensors outside the local aerodrome without prior approval Signup and view all the answers

What is the primary purpose of MAJCOM approval for using FBWOS at locations other than controlled airfields?

To ensure safe and efficient weather reporting Signup and view all the answers

What is the primary function of the FBWOS system in automated mode?

To sense, report, and measure atmospheric weather elements Signup and view all the answers

What is the estimated cloud base height (ft) when the surface dewpoint is 7.0°C?

3,000 Signup and view all the answers

What unit is used to report altimeter settings in the United States and at US military organizations overseas?

Inches of mercury (iHg) Signup and view all the answers

Who is responsible for coordinating site acceptance and commissioning at locations with DAF-owned FBWOS, but no DAF weather personnel assigned?

The sponsoring MAJCOM, Lead Command, and the Program Managers Office Signup and view all the answers

What is the significance of the four-digit group immediately following the A in the altimeter encoding?

It indicates the altimeter setting in inches of mercury. Signup and view all the answers

What is the primary purpose of the site acceptance and commissioning process?

To achieve operational readiness of the FBWOS system Signup and view all the answers

What is the primary consideration for siting FBWOS sensor groups?

To conform to the Unified Facilities Criteria 3-260-1 Signup and view all the answers

What is the purpose of Chapter 13 of AFMAN15-111?

To describe the observing and reporting standards for pressure measurements. Signup and view all the answers

What is the estimated cloud base height (ft) when the estimated cloud surface dewpoint is 12.0°C?

4,800 Signup and view all the answers

What is the unit of measurement used for station pressure?

Inches of mercury (iHg) Signup and view all the answers

What is the purpose of the altimeter group in pressure reporting?

To indicate the altimeter setting in inches of mercury. Signup and view all the answers

What is the estimated cloud base height (ft) when the surface dewpoint is 4.0°C?

1,600 Signup and view all the answers

What is the maximum interval for disseminating an ALSTG LOCAL observation when there has been a change of 0.01 inches of mercury or more since the last disseminated ALSTG value?

35 minutes Signup and view all the answers

What sections make up a complete METAR/SPECI coded report?

Body and Remarks Signup and view all the answers

What indicates a required space between the groups in the METAR/SPECI code?

An underscore Signup and view all the answers

What fulfills the requirement for disseminating an ALSTG LOCAL observation at an interval not to exceed 35 minutes?

A METAR or SPECI taken within the established time interval Signup and view all the answers

What establishes the contents of LOCALs taken and disseminated to agencies other than ATC?

All of the above Signup and view all the answers

How often should WFs/Dets disseminate an ALSTG LOCAL observation when there has been a change of 0.01 inches of mercury or more since the last disseminated ALSTG value?

When there has been a change of 0.01 inches of mercury or more Signup and view all the answers

What is the primary purpose of a METAR/SPECI observation?

To provide weather information to ATC agencies Signup and view all the answers

What is contained in a single element observation of an ALSTG LOCAL?

The time and ALSTG Signup and view all the answers

When is back-up required during uncontrolled airfield hours?

When elements triggering weather warnings are erroneously reported and/or when required for supplementation criteria Signup and view all the answers

What happens when unreliable values from any equipment are reported?

They are considered missing if they cannot be determined through other methods Signup and view all the answers

What is required to use the AN/TMQ-53 as a primary or back-up?

Both good working condition and proper maintenance IAW the T.O. Signup and view all the answers

What is the purpose of back-up equipment?

To back-up the primary certified observing systems Signup and view all the answers

When is back-up not required?

During uncontrolled airfield hours when elements triggering weather warnings are not erroneously reported Signup and view all the answers

What is not allowed when backing-up malfunctioning sensors?

Replace the entire automated observation with a manual observation Signup and view all the answers

What is the condition for using manual observing equipment?

According to this manual and the applicable T.O. or user manual Signup and view all the answers

What should weather personnel do when backing-up malfunctioning sensors?

Follow guidance in Attachment 2 and Attachment 3 and report the individual required elements Signup and view all the answers

What is the format of encoding vertical visibility?

VVhshshs, where VV identifies an indefinite ceiling and hshshs is the vertical visibility in hundreds of feet Signup and view all the answers

What does CLR or SKC represent in the sky condition report?

Clear skies Signup and view all the answers

How are the layers separated in the sky condition report?

By spaces Signup and view all the answers

What is the layer height of a surface-based obscuration?

000 Signup and view all the answers

How does an FBWOS derive sky condition?

By detecting the frequency and height of clouds over a 30-minute period Signup and view all the answers

What is the limitation of FBWOS sensors?

They may perform poorly in situations where clouds develop in the vertical but have little horizontal movement Signup and view all the answers

How is a partial obscuration encoded in the sky condition report?

By using the reportable layer construction corresponding to the amount of the sky that is obscured followed by the layer height Signup and view all the answers

What is appended to the report for surface-based obscurations?

A remark Signup and view all the answers

When is the AF Weather-Web Service (AFW-WEBS) used for dissemination of observations longline?

During periods when the ADS is unavailable Signup and view all the answers

What is disseminated locally when required?

Pressure altitude (PA) and density altitude (DA) with the exception of runway condition remarks Signup and view all the answers

What is the correct format for transmitting corrections (COR) to transmitted data?

Using the entire corrected observation with the original date and time Signup and view all the answers

What is the purpose of disseminating corrections (COR) to transmitted data?

To correct errors in transmitted reports Signup and view all the answers

What is included in the augmented observation in Figure 3.2?

METAR, SPECI, and additional data Signup and view all the answers

When is it necessary to disseminate pressure altitude (PA) and density altitude (DA)?

When required Signup and view all the answers

What is the purpose of using the OWS or another WF/Det to disseminate observations longline?

As a backup when the ADS is unavailable Signup and view all the answers

What is the significance of the original date and time in the corrected observation?

It is used to indicate the time of the original observation Signup and view all the answers

What is the significance of the hectopascal values in the table?

They are the truncated values to their reportable value (i.e. rounded down to the nearest whole hPa) Signup and view all the answers

What is the primary method for determining Sea-Level Pressure (SLP)?

By taking a direct reading from the FBWOS. Signup and view all the answers

What happens to the pressure values when they are reported?

They are truncated to their reportable value (i.e. rounded down to the nearest whole hPa). Signup and view all the answers

What is the unit of measurement used for station pressure and altimeter settings in the United States and at US military organizations overseas?

Inches of mercury. Signup and view all the answers

What is the primary measurement of atmospheric pressure used in observations?

Station pressure. Signup and view all the answers

What is the primary method for determining Pressure Altitude (PA) and Density Altitude (DA)?

By calculating the pressure altitude and density altitude from the atmospheric pressure values. Signup and view all the answers

What is the format for reporting rapid pressure changes in the remarks of the observation?

PRESRR xxxyy Signup and view all the answers

What is the purpose of a barometer comparison/calibration program?

To ensure the accuracy of the pressure values reported. Signup and view all the answers

What should weather personnel do when augmenting an observation?

Use manual observing methods to determine and report the elements of an observation. Signup and view all the answers

What is the purpose of documenting augmented observations?

To record the elements of an observation that were edited or added. Signup and view all the answers

What should weather personnel do when they are no longer required to augment an observation?

Reconfigure the ADS to disseminate in automated mode. Signup and view all the answers

What is the purpose of ADS (JET) Form 3813?

To document augmented weather observations. Signup and view all the answers

What is the significance of having a view of the airfield complex and situational awareness of the current conditions?

It allows weather personnel to accurately report the weather conditions. Signup and view all the answers

What is the purpose of supplementing an FBWOS?

To provide additional data to the FBWOS-generated observation. Signup and view all the answers

What should weather personnel use to determine the elements of an observation when augmenting?

Manual observing methods. Signup and view all the answers

Why should WFs/Dets not use inactive/parallel runway equipment to back-up a faulty RVR reading?

Because it is not intended for that purpose. Signup and view all the answers

During uncontrolled airfield hours, who is responsible for responding to severe weather events?

Weather personnel Signup and view all the answers

What takes precedence over all other phenomena in terms of immediate reporting?

Tornadic activity Signup and view all the answers

When is a tower visibility remark required?

Only during controlled airfield hours Signup and view all the answers

What is the frequency at which weather personnel should check the weather during controlled airfield hours?

At intervals not to exceed 20 minutes Signup and view all the answers

What should weather personnel do when supplementing observations?

Ensure that all applicable element entries are made in the body of the observation along with accompanying remarks Signup and view all the answers

What is the purpose of Table 5.1?

To list mandatory supplementation conditions Signup and view all the answers

When should weather personnel supplement observations for Sandstorms/Dust Storms?

Whenever a local warning for the conditions is required Signup and view all the answers

What is the purpose of a Severe Weather Action Plan (SWAP)?

To respond to severe weather events during uncontrolled airfield hours Signup and view all the answers

What is the format for encoding wind gusts in whole knots?

Gfmfm(fm) Signup and view all the answers

What is the purpose of using 5-second average wind directions and speeds in wind algorithms?

To compute and report the 2-minute average wind direction and speed Signup and view all the answers

What is the format for encoding variable wind direction with wind speed greater than 6 knots?

dndndnVdxdxdx Signup and view all the answers

What is the unit of measurement used for wind speed in wind encoding?

Knots Signup and view all the answers

What is the purpose of determining wind direction in wind algorithms?

To determine wind shifts and the range of variability Signup and view all the answers

What is the format for encoding calm wind?

00000KT Signup and view all the answers

What is the purpose of FBWOS sensors?

To determine wind direction, speed, gusts, wind shifts and peak wind at all automated observing locations Signup and view all the answers

What is the method used to determine wind direction?

Averaging the direction the wind is coming from with regards to true north over a 2-minute period Signup and view all the answers

What code figure represents an atmospheric pressure that is now higher than 3 hours ago and is increasing steadily or unsteadily?

2 Signup and view all the answers

What code figure represents a decreasing atmospheric pressure that is now lower than 3 hours ago and is decreasing steadily or unsteadily?

7 Signup and view all the answers

What code figure represents an atmospheric pressure that is now the same as 3 hours ago and is steady?

4 Signup and view all the answers

What code figure represents an atmospheric pressure that is increasing, then decreasing?

0 Signup and view all the answers

What code figure represents an atmospheric pressure that is decreasing, then increasing?

5 Signup and view all the answers

What code figure represents an atmospheric pressure that is increasing, then steady, or increasing then increasing more slowly?

1 Signup and view all the answers

What code figure represents an atmospheric pressure that is decreasing, then steady, or decreasing then decreasing more slowly?

7 Signup and view all the answers

What code figure represents an atmospheric pressure that is steady or increasing, then decreasing, or decreasing then decreasing more rapidly?

8 Signup and view all the answers

What is the unit of measurement used for station pressure in locations where it is determined?

Hectopascals Signup and view all the answers

How are Pressure Altitude (PA) and Density Altitude (DA) computed?

Automatically by FBWOSs Signup and view all the answers

What is the difference between the formula used by JET and FBWOS to compute Density Altitude?

JET takes into account water vapor, while FBWOS does not Signup and view all the answers

When should ATC agencies be notified that the reported PA and DA values are estimated?

When the primary pressure sensor is inoperative Signup and view all the answers

What is the purpose of a barometer comparison/calibration program?

To ensure the accuracy of barometric measurements Signup and view all the answers

When should comparisons be delayed during barometer calibration?

During periods of high wind speeds Signup and view all the answers

What is the format for reporting rapid pressure changes in the remarks of the observation?

Using the format in Attachment 3 Signup and view all the answers

What is the purpose of recording and documenting barometer comparisons?

To ensure the accuracy of barometric measurements Signup and view all the answers

During which hours will weather personnel supplement observations?

Controlled airfield hours Signup and view all the answers

What is the maximum time interval between checks for mandatory supplemental criteria?

20 minutes Signup and view all the answers

What is the primary purpose of a SPECI report?

To provide additional information about weather conditions that meet special criteria Signup and view all the answers

When should a SPECI report be prepared and transmitted?

As soon as possible after the relevant criteria are observed Signup and view all the answers

What is the purpose of the Severe Weather Action Plan (SWAP)?

To respond to severe weather events during uncontrolled airfield hours Signup and view all the answers

What is the primary purpose of using unfocused lights of moderate intensity as nighttime visibility markers?

To avoid glare from focused lights Signup and view all the answers

What is the time ascribed to a SPECI report?

The time, to the nearest minute, that the SPECI criteria are first met or observed Signup and view all the answers

What should WFs/Dets provide to assist in preparing a visibility checkpoint chart or list of visibility markers?

A list of suitable objects Signup and view all the answers

When is the immediate reporting of tornadic activity required?

Whenever a tornado watch is valid or warning has been issued Signup and view all the answers

What is the criterion for reporting Sandstorms/Dust Storms?

Whenever a local warning for the conditions is required Signup and view all the answers

What is the basis for SPECI criteria?

Published take-off, landing, and circling airfield minima Signup and view all the answers

What should be done immediately upon notification of an aircraft mishap?

Encode and disseminate a full element SPECI Signup and view all the answers

What is the purpose of collecting and saving data related to an aircraft mishap?

To assist in the investigation Signup and view all the answers

What is required for supplementing observations?

Accompanying remarks and applicable element entries in the body of the observation Signup and view all the answers

What is a LOCAL report?

An unscheduled weather report that does not meet SPECI criteria Signup and view all the answers

What type of weather phenomenon requires a tower visibility remark?

All phenomena during controlled airfield hours Signup and view all the answers

When is a LOCAL report taken?

When unit leadership determines it is necessary Signup and view all the answers

What is the temporary measure when an aircraft is authorized to land on an inactive runway?

Requesting observation data from the inactive runway Signup and view all the answers

Why are focused lights such as airway beacons not suitable as nighttime visibility markers?

Due to their intensity Signup and view all the answers

What is the purpose of a SWAP during uncontrolled airfield hours?

To respond to severe weather threats Signup and view all the answers

In what format are LOCAL reports encoded?

METAR format Signup and view all the answers

What is the purpose of SPECI and LOCAL reports?

To support local operations and aircraft operations Signup and view all the answers

What should WFs/Dets do when an aircraft is involved in an in-flight emergency?

Alert weather personnel to be prepared to take a SPECI Signup and view all the answers

What is the purpose of control tower visibility aids?

To assist in determining tower visibility Signup and view all the answers

What is the primary reason for not using inactive/parallel runway equipment to back-up a faulty RVR reading?

To conform to AFMAN15-111 guidelines Signup and view all the answers

What is the primary responsibility of weather personnel when augmenting an observation?

To maintain situational awareness of the airfield complex Signup and view all the answers

What is the purpose of configuring ADS to disseminate in augmented or manual mode?

To remove the 'AUTO' report modifier from the observation Signup and view all the answers

What is the primary method for determining the elements of an observation when augmenting?

Using manual observing methods Signup and view all the answers

What is the purpose of documenting augmented observations using forms such as AF Form 3803?

To provide a record of weather observations Signup and view all the answers

What is the primary advantage of using electronic workbooks for documenting augmented observations?

Increased accuracy and efficiency Signup and view all the answers

What is the primary consequence of not reconfiguring ADS to disseminate in automated mode when augmentation is no longer required?

The 'AUTO' report modifier is not removed Signup and view all the answers

What is the primary purpose of Chapter 5 of AFMAN15-111?

To describe the requirements for observation augmentation Signup and view all the answers

What is the pressure characterization code figure for atmospheric pressure that is now higher than 3 hours ago?

1 Signup and view all the answers

What does a pressure characterization code figure of 4 indicate?

Atmospheric pressure is steady Signup and view all the answers

What is the pressure characterization code figure for atmospheric pressure that is now lower than 3 hours ago and decreasing steadily or unsteadily?

7 Signup and view all the answers

What is the pressure characterization code figure for atmospheric pressure that is decreasing, then increasing; or increasing then increasing more rapidly?

3 Signup and view all the answers

What is the pressure characterization code figure for atmospheric pressure that is increasing steadily or unsteadily?

2 Signup and view all the answers

What is the pressure characterization code figure for atmospheric pressure that is decreasing, then steady; or decreasing then decreasing more slowly?

6 Signup and view all the answers

What is the pressure characterization code figure for atmospheric pressure that is steady or increasing, then decreasing; or decreasing then decreasing more rapidly?

8 Signup and view all the answers

What is the pressure characterization code figure for atmospheric pressure that is increasing, then decreasing?

0 Signup and view all the answers

Study Notes

Visibility and Observations

Surface-based obscurations are considered when the prevailing visibility is the same as at the control tower level.
Tower visibility remark is included in the next METAR or SPECI when the surface prevailing visibility or control tower visibility is less than 4 SM (6000 m) and differs from the surface prevailing visibility by a reportable value.

Visibility Reference Tools

Visibility reference tools should be high-quality color photographs taken on a cloud-free and obscuration-free day.
Photographs should be supplemented with map-type visibility charts to aid in observation.
Visibility markers should be clearly identified with distance, direction, and day/nighttime aids.

Pressure Measurement

FBWOS sensors measure barometric pressure and compute pressure parameters (e.g., station pressure, altimeter setting, and sea-level pressure).
Pressure values are rounded down to the nearest reportable value.
Pressure data is expressed in inches of mercury (iHg) in the United States and hectopascals (hPa) for sea-level pressure.

Altimeter Setting and Pressure Altitude

Altimeter setting is included in the body of the observation.
Pressure altitude (PA) and density altitude (DA) are automatically computed by FBWOS and disseminated to ATC agencies.
PA and DA can be computed using OWS or AFW-WEBS Forecaster Tools if primary method is unavailable.

Rapid Pressure Changes

FBWOS/JET automatically detect rapid pressure changes and enter a remark in the observation.
If primary pressure sensor is inoperative, notify ATC agencies that reported PA and DA values are estimated.

Barometer Comparison and Calibration

Each unit with an AN/TMQ-53 or hand-held barometer should establish a comparison/calibration program.
Comparisons should be delayed during periods of high wind speeds, rapid temperature changes, or steep horizontal and/or vertical temperature gradients.

Longline Dissemination

When an augmented observation cannot be transmitted longline, transmit only the latest observation longline.
Enter "FIBI" (Filed But Impractical to Transmit) in column 13 of the observation form if a later observation containing all elements of a METAR is available for transmission.

SPECI Reports

When a SPECI is not transmitted longline, transmit subsequent SPECI only when the change between the last transmitted report and the current report meets the criteria for a SPECI.
Otherwise, enter (FIBI) in remarks for the current report and only disseminate it locally.

Reports of Volcanic Eruptions

Reports of volcanic eruptions are disseminated regardless of the delay.
Use any reasonable means to disseminate the report.

General Observing Information

All primary meteorological equipment used in the generation of surface weather observations must operate in automated mode at AF and Army controlled airfields.

Weather Observing Systems (FBWOS)

FBWOS operate in automated mode to provide official METAR and SPECI observations with augmentation when required.
Siting and exposure of equipment are critical for accurate data collection.

Wind Observation

Wind direction is determined manually using a compass or digital measuring device, taking a 2-minute average reading.
Wind speed is determined manually using an approved anemometer, taking a 2-minute average reading.
If an instrument is not available, use the Beaufort scale to determine wind speed.

Sky Condition

Sky condition is an evaluation of all obscurations/clouds making up layers at different heights and is reported in oktas (eighths).
Clouds and/or obscuring phenomena with bases at approximately the same level constitute a layer.
Heights of layers are reported using a three-digit value representing hundreds of feet above the surface.

Pressure Reports

Station pressure is the atmospheric pressure computed for the level of the station elevation.
Altimeter setting is a computed pressure value that an aircraft altimeter scale is set to, indicating the altitude above MSL of an aircraft on the ground.
Sea-level pressure (SLP) is a report of the theoretical reduction of station pressure to sea level.
Pressure tendency is a coded report included on the 3-hourly observations that indicates the characteristic and amount of pressure change during the 3-hour period preceding the observation.

Observation Point and Rounding of Figures

The point of observation is the location of primary and discontinuity sensor groups for objective elements and the designated point used by WF/Det personnel to evaluate subjective elements and back-up sensed objective elements as needed.
Figures and values should be rounded to the nearest reportable value using the round half up method.
Examples of rounding:
- 1.5 becomes 2
- -1.4 becomes -1
- 1.3 becomes 1
- -2.6 becomes -3

Cloud Height and Visibility Values

When cloud height and visibility values are less than or equal to halfway between two reportable values, report the lower value.
Examples:
- Cloud heights of 2,549 ft and 2,550 ft are reported as 2,500 ft
- Visibility values of 5 1/4 SM (8250 m) and 5 1/2 SM (8500 m) are reported as 5 SM (8000 m)

Pressure Values

When computations of pressure values require rounding to comply with standards of reportable values, the number is always rounded down to the next reportable value.
Examples:
- A station pressure reading of 29.249 is rounded down to 29.245
- 29.244 is rounded down to 29.240
- ALSTGs of 29.249 and 29.244 are both truncated to 29.24
Pressure values for international aviation purposes and reported in hPa are always rounded down and reported as whole numbers.
Example: 1009.9 hPa and 1009.1 hPa are both truncated to 1009 hPa

Dissemination

Wind direction is disseminated in degrees magnetic using three digits.
All other plain language remarks are disseminated as required by local agencies after the last element of the observation.
A copy of all observations disseminated locally should be maintained.
Voice dissemination instructions should outline priorities and procedures to follow for local dissemination of observations by voice relay.
Disseminate all observations immediately to local ATC agencies and then to other users as established locally.

Supplementary Identification of Observations

At limited-duty manual WFs/Dets and gunnery ranges, identify the last observation of the day (METAR or SPECI) by adding the term "LAST" following the last element in the observation text.

Delayed Reports

When it is evident that a weather report will not be completed in time for scheduled transmission, transmit the contraction NIL at the standard time.

Sky Cover Code Forms

Sky cover code forms reflect the degree of sky coverage based on a summation of the amount of clouds/obscuring phenomena at and below the layer being evaluated.
Approved code forms are:
- Sky Clear (SKC or CLR) - 0/8ths coverage
- Few (FEW) - A trace through 2/8ths coverage
- Scattered (SCT) - 3/8ths through 4/8ths coverage
- Broken (BKN) - 5/8ths through less than 8/8ths coverage
- Overcast (OVC) - 8/8ths coverage
- Vertical Visibility (VV) - The sky is completely covered by a surface-based phenomenon; 8/8ths coverage

Ceiling

For aviation purposes, the reported ceiling is defined as the lowest height at which the summation of layers equals broken or greater coverage (> 5/8ths) or the maximum height that can be observed into a vertical visibly obscuration.

Pressure Conversion Table

The pressure conversion table provides a conversion from inches of mercury to hectopascals.

Sea-Level Pressure

Determine the sea-level pressure by taking a direct reading from the FBWOS. If a direct readout is unavailable, SLP is computed using the current station pressure and the locally designated method.

Pressure Tendency

Determine the pressure tendency by taking a direct reading from the FBWOS during the 3-hourly observations.
If a direct readout of the pressure tendency is unavailable, compute the tendency using the 3-hour trend of the ALSTGs and the pressure difference from the 3-hour period.

Aviation Weather Code Forms

Aviation Routine Weather Report (METAR) is a routine scheduled observation used to report surface meteorological data.
METARs contain a complete report of wind, visibility, runway visual range (RVR), present weather, sky condition, temperature, dew point, and altimeter setting.
METAR remarks (RMK) section provides additional information that elaborates on data in the body of the observation.
WF/Dets operate with established METAR file times between 55 to 59 minutes past the hour.
METAR observations taken at 0000, 0600, 1200, and 1800 UTC include additional data and are known as “6-hourly observations.”
METAR observations taken at 0300, 0900, 1500, and 2100 UTC also contain additional information and are known as “3-hourly observations.”

Aviation Selected Special Weather Report (SPECI)

SPECI reports provide additional information on weather phenomena such as tornadoes.
Distance may be included in the remark for SPECI reports.
Movement of clouds or weather is encoded with respect to direction when known.

Observation Methods

Automated Observations:
- Use time averaging of sensor data.
- Sky condition is evaluated during the 30-minute period ending at the actual time of observation.
- Other elements are based on sensor data within 10 minutes or less of the actual time of observation.
- One-Minute Observation (OMO) is generated every minute and includes all basic weather parameters.
Augmented Observations:
- Use a fixed time, spatial averaging technique for evaluating subjective elements.
- Individual elements must reflect conditions existing at the actual time of observation.
- Observations are made as close to the scheduled time as possible, but not more than 15 minutes before.

Magnetic Declination

Local magnetic declination must be determined at each observing location to convert wind direction from magnetic to true.
Local declination changes by several minutes of arc each year at most locations.
Weather leadership must monitor FLIPs or revised charts for changes in local magnetic declination.

FBWOS (Full-Body Weather Observation System)

FBWOSs are certified as conforming to station certification requirements.
Site acceptance and commissioning are accomplished by the host-installation AF weather organization.
FBWOSs can be used at locations other than controlled airfields with MAJCOM approval.
FBWOSs report and measure weather elements such as wind speed and direction, visibility, thunderstorms, precipitation, obscurations to visibility, sky cover, cloud height, temperature, dew point, and altimeter setting.

SPECI and LOCAL Weather Reports

A SPECI (Special Weather Report) is an unscheduled observation that is completed and transmitted when special criteria are met or sensed.
SPECI reports contain all elements of a METAR (Aviation Routine Weather Report) plus additional remarks.
All SPECI reports are prepared and transmitted as soon as possible after the relevant criteria are observed.
The time of a SPECI report reflects the time the criteria are first met or observed.

METAR and SPECI Report Format

A METAR report includes the following elements:
- Type of report (METAR or SPECI)
- Station identifier (CCCC)
- Date and time of report (YYGGggZ)
- Report modifier (COR or AUTO)
- Wind information (dddff(f)Gfmfm(fm)KT_dndndnVdxdxdx)
- Visibility information (VVVVSM or VVVV)
- Runway visual range information (RDRDR[DR]//VRVRVRVRFT or RDRDR[DR]/VNVNVNVNVVXVXVXVXFT)
- Present weather information (w'w')
- Sky condition information (NsNsNshshshs or VVhshshs or CLR)
- Temperature and dew point information (T'T'/T'dT'd)
- Altimeter information (APHPHPHPH)
- Remarks (RMK)

Automated Dissemination System (ADS)

An ADS is any system capable of disseminating observations for use by operational customers.
The primary ADS at most Air Force Weather operating locations is the Joint Environmental Toolkit (JET) platform.

FBWOS Certification Requirements

The FBWOS commissioning process consists of four phases: installation, acceptance, activation, and operational capability.
Certification of the weather flights concludes with the weather certification official declaring their weather flight is ready to operate using the FBWOS and the designated commander declaring initial operating capability (IOC).
The weather certification official must be satisfied with system performance, level of proficiency of flight personnel, and maintenance support capability to declare IOC.

Reporting and Encoding Weather Observations

METAR (Aviation Routine Weather Report) is a routine scheduled observation that contains a complete report of wind, visibility, runway visual range (RVR), present weather, sky condition, temperature, dew point, and altimeter setting.

METAR Observations

METARs are taken at established file times between 55 to 59 minutes past the hour.
"6-hourly observations" include additional data and are taken at 0000, 0600, 1200, and 1800 Coordinated Universal Time (UTC).
"3-hourly observations" also contain additional information and are taken at 0300, 0900, 1500, and 2100 UTC.

Aviation Selected Special Weather Report (SPECI)

SPECI is used to correct a previously disseminated report, and the corrected report will use the same time as the report being corrected.
The date and time group always ends with a "Z", indicating the use of UTC.

Report Modifier (AUTO or COR)

COR is entered into the report modifier group when a corrected METAR or SPECI is transmitted.
AUTO identifies the report as a fully automated report with no human intervention.

Coding Missing Data in METAR and SPECI Reports

When an element does not occur or cannot be observed, the corresponding group and preceding space are omitted from the report.
A missing data flag (M) is automatically included in the corresponding data field if an element cannot be provided due to sensor failure.

Remarks (RMK)

Remarks elaborate on parameters reported in the body of the report and are included if required.
The distance may be included in the remark, and the exact location should be included when possible, such as in the case of a tornado.

Observation Methods

Automated observations use time averaging of sensor data.
Sky condition is an evaluation of sensor data gathered during the 30-minute period ending at the actual time of the observation.
The One-Minute Observation (OMO) is a fully automated report that includes all of the basic weather parameters found in the body of the METAR.

Aircraft Mishap

Upon notification of an aircraft mishap, WFs/Dets will immediately encode and disseminate a full element SPECI.
A SPECI is not required for an in-flight emergency (IFE), but weather personnel should be prepared to take a SPECI if the IFE becomes a mishap.

Inactive/Parallel Runway Equipment

Supplemental data may be requested by ATC if an aircraft is authorized to land using an inactive runway with installed weather sensors.

Supplementation of Observations

Weather personnel will supplement observations during controlled airfield hours and check the weather at intervals not to exceed 20 minutes whenever mandatory supplemental criteria are observed or forecast to occur within 1 hour.
Mandatory supplementation conditions include tornadoes, waterspouts, funnel clouds, freezing precipitation, ice pellets, hail, sandstorms, dust storms, volcanic ash, and tower visibility remarks.

Back-up Procedures

Weather personnel will follow locally developed guidance and procedures in DAFMAN 15-129, Air and Space Weather Operations, to collect and save data related to an aircraft mishap.

Procedures for Task Certified ATC Personnel

Report changes in tower visibility when it is less than 4 SM (6000 m) and differs from the prevailing visibility by at least one reportable value.
Relay PIREPs as soon as practical, within ATC established duty priorities.

Control Tower Observations

Task certified ATC personnel must take tower visibility observations when the prevailing visibility at the point of observation or at the tower level is less than 4 SM (6000 m).
Notify the weather technician when the observed tower prevailing visibility decreases to less than 4 SM (6000 m) or increases to or exceeds 4 SM (6000 m).

Weather Personnel

Evaluate prevailing visibility as soon as practicable upon receipt of tower visibility report that differs from the latest reported surface visibility.
Use tower visibility values as a guide in determining the surface visibility when portions of the horizon are obstructed by buildings, aircraft, etc.

Supplemental Data

Use of data from inactive runway sensors must be based on the following factors:
- Supplemental RVR data for an inactive runway can be reported in the remarks section of an observation.
- Supplemental wind data for an inactive/parallel runway can be reported in the remarks section of an observation when there is at least a 6 knot (kt) difference in speed (sustained or gusts) between the active wind sensor and the inactive sensor(s).
- Cloud heights generally do not differ from one end of a runway to the other.
- Supplemental temperature data for an inactive/parallel runway can be reported in the remarks section of an observation when the difference is at least one reportable value between the active and inactive sensor.

Atmospheric Pressure

Table 13.4 shows the amount of pressure change in the last 3 hours.
Retain the last two barometer comparisons on file and dispose of all others.

Deployable Barometers

Compare barometers against a standard barometer at a minimum of annually, before deployment, when first deployed, if relocated during a deployment, and as soon as practical after redeployment.
Determine a mean correction by making at least four comparisons, not less than 15 minutes apart, against the standard barometer.
Apply the mean correction (or adjust the software to reflect the correction) to a fifth pressure reading.

Weather Certification and Station Information

The weather certification official prepares a memo for the commander's signature, recommending commissioning of the FBWOS, with the new station information file attached.
The signed commissioning document and attachments are sent to 14 WS/DOD and 2 SYOS/SYSD, with a copy retained in the flight's permanent historical file.

Position Qualification Requirements

Weather personnel are trained, task-certified, and position-qualified according to applicable Career Field Education and Training Plan, Talent Management Framework, and local training requirements and plans.
Weather personnel task-certify ATC personnel to evaluate tower visibility values from the control tower.
Weather personnel ensure DAF ATC personnel can operate applicable weather equipment located inside DAF ATC facilities.

Station Information File and Accuracy of Time

The station information file is emailed to [email protected] and [email protected] or mailed to 14WS/WXD, 151 Patton Avenue, Asheville, NC 28801-5002.
The accuracy of time ascribed to weather observations is crucial, especially in aviation safety investigations.
The standard clock is a standalone clock zeroed with the US Naval Observatory time (DSN: 312-762-1401) or a computer network clock verified to be synchronized with a GPS or Naval Observatory clock.

Procedures for Task-Certified ATC Personnel

Task-certified ATC personnel report changes in tower visibility when it is less than 4 SM (6000 m) and differs from the prevailing visibility by at least one reportable value.
ATC personnel relay PIREPs as soon as practical, within ATC established duty priorities.
As part of the cooperative weather watch, WFs/Dets notify airfield leadership that the RVR system requires runway lights to be left on to work properly during continuous RVR reporting outside controlled airfield hours.

Control Tower Observations

Task-certified ATC personnel take tower visibility observations when the prevailing visibility at the point of observation or at the tower level is less than 4 SM (6000 m).
Weather personnel evaluate prevailing visibility as soon as practicable upon receipt of tower visibility report that differs from the latest reported surface visibility.
Weather personnel use tower visibility values as a guide in determining surface visibility when portions of the horizon are obstructed.

Supplementing Observations

Weather personnel supplement observations during controlled airfield hours and check the weather at intervals not to exceed 20 minutes whenever mandatory supplemental criteria are observed or forecast to occur within 1 hour.
Mandatory supplemental criteria include tornado (+FC), waterspout (+FC), funnel cloud (FC), freezing precipitation (FZDZ/FZRA), ice pellets (PL), hail (GR), sandstorm (SS)/dust storm (DS), and volcanic ash (VA).

Station pressure is defined as the atmospheric pressure computed for the level of the station elevation.
The altimeter setting is a computed pressure value that an aircraft altimeter scale is set to so it indicates the altitude above MSL of an aircraft on the ground at the location for which the value was determined.
Additional derived pressure-related reports include sea-level pressure (SLP), pressure tendency, pressure altitude (PA), and density altitude (DA).

Pressure Altitude (PA) and Density Altitude (DA)

PA and DA are automatically computed by FBWOSs, displayed on ADS (e.g., JET) and TMQ-53 sensor displays, and disseminated locally to ATC agencies.
PA and DA can also be computed using the OWS or AFW-WEBS Forecaster Tools if a direct readout of the primary method is unavailable.

Comparison and Calibration Procedures

Each unit with an AN/TMQ-53, a hand-held barometer, and/or equivalent establishes a barometer comparison/calibration program.
Barometer comparisons are recorded and documented on a locally developed worksheet/spreadsheet or MAJCOM or higher headquarters approved form/worksheet/spreadsheet.

Dissemination of METAR/SPECI Observations

Most Weather Flights/Detachments (WFs/Dets) use an Automated Dissemination System (ADS) as the primary local and longline dissemination system.
During ADS outages, use AF Weather-Web Service (AFW-WEBS), the Operational Weather Squadron (OWS), or another WF/Det to disseminate observations longline.

Pressure Altitude and Density Altitude

Pressure altitude (PA) and density altitude (DA) are disseminated locally.
When required, disseminate PA (e.g., PA +130) or DA (e.g., DA +3680) following the last element or remark in the observation, with the exception of runway condition remarks which are reported last.

Corrections (COR) to Transmitted Data

Disseminate CORs in the same manner as the observation being corrected as soon as possible whenever an error is detected in a transmitted report.
However, if the erroneous data has been corrected or superseded by a later report (with the same or more complete dissemination), do not transmit the corrected observation.

Local Dissemination

During ADS outages or if ADS is not available, disseminate observations to ATC first.
For further dissemination, establish procedures locally in an order of priority that is consistent with local requirements and scheduled file times for longline transmission.

FBWOS Sensor Siting

FBWOS sensor groups are sited in accordance with the Unified Facilities Criteria 3-260-1 (UFC 3-260-1), Airfield and Heliport Planning and Design.
Previously installed sensors may be operated at their present locations; however, if they are relocated, siting will be in accordance with the federal standard.

Commissioning of FBWOS

Each site will conform to the site acceptance procedures and commission their FBWOS.
At locations with assigned AF weather personnel, site acceptance and commissioning will be accomplished by the host-installation AF weather organization.
At locations with a DAF-owned FBWOS, but no DAF weather personnel assigned, the sponsoring MAJCOM, Lead Command, and the Program Managers Office will coordinate site acceptance and commissioning with appropriate technical experts and mission owners utilizing the appropriate host service or agency as needed.

AN/TMQ-53s

AN/TMQ-53s are used for tactical airfields, or as long-term backup (72-hours or greater) for fixed meteorological sensors (when sited appropriately) at AF and Army controlled airfields.
AN/TMQ-53s will not be used as standalone weather sensors outside the local aerodrome, without prior approval from their parent MAJCOM.

FBWOS System

In the automated mode, the FBWOS system continually senses, reports, and measures the atmosphere for various weather elements.

Visibility Reference Tools

Visibility reference tools that are photographs should be high-quality color photos taken on a predominantly cloud and obscuration-free day.
It is recommended to develop map-type visibility charts to augment the photographic visibility markers.

Glossary of References and Supporting Information

The glossary includes a list of references, prescribed forms, adopted forms, abbreviations, and acronyms used in the document.

Tower Visibility Observations

Task certified ATC personnel report changes in tower visibility when it is less than 4 SM (6000 m) and differs from the prevailing visibility by at least one reportable value.
ATC personnel relay PIREPs as soon as practical, within ATC established duty priorities.

Control Tower Observations

ATC directives require task certified ATC personnel to take tower visibility observations when the prevailing visibility at the point of observation or at the tower level, is less than 4 SM (6000 m).
Control tower personnel notify the weather technician when the observed tower prevailing visibility decreases to less than 4 SM (6000 m) or increases to or exceeds 4 SM (6000 m).

Weather Personnel

Weather personnel evaluate prevailing visibility as soon as practicable upon receipt of tower visibility report that differs from the latest reported surface visibility.
Weather personnel use tower visibility values as a guide in determining the surface visibility when portions of the horizon are obstructed by buildings, aircraft, etc.

Visibility Aids

The most suitable nighttime visibility markers are unfocused lights of moderate intensity.
Runway course lights and TV/radio/water tower obstruction lights make good markers.

Aircraft Mishap

Upon notification of an aircraft mishap, WFs/Dets immediately encode and disseminate a full element SPECI in accordance with Attachment 2.
WFs/Dets follow locally developed guidance and procedures in DAFMAN 15-129 to collect and save data related to the mishap.

Inactive/Parallel Runway Equipment

ATC may occasionally authorize an aircraft to land using an inactive runway, and may initiate a request for observation data to control aircraft using that runway.

Observation Augmentation

Augmentation is the process of having position-qualified weather personnel edit or add additional data to an observation generated by an FBWOS.
Weather personnel must have a view of the airfield complex and maintain situational awareness of the current conditions as well as the FBWOS-sensed data and observations.

Supplementing FBWOSs

Wind direction is reported using a 3-digit compass heading rounded to the nearest 10 degrees, or when meeting criteria, may be reported as variable (VRB).
Wind speed is determined by averaging the speed over a 2-minute period and is reported in whole knots.
Wind gusts are determined by evaluating the most recent 10-minutes of wind speed data for rapid fluctuation in speed with a variation of 10 knots or more between peaks and lulls.

Manual Observing Methods

Predominant wind direction, speed, gusts, and shifts are determined by the primary active wind sensor; peak wind data is determined by all available runway sensors.
Wind shifts are a change in direction by at least 45 degrees that occurs in less than 15 minutes and has sustained winds of at least 10kts throughout the shift.

Dissemination of Weather Observations

Most Weather Forces/Detachments (WFs/Dets) use Automated Dissemination System (ADS) as the primary local and longline dissemination system.
During ADS unavailability, use AF Weather-Web Service (AFW-WEBS), Operational Weather Squadron (OWS), or another WF/Det to disseminate observations longline.

Pressure Altitude and Density Altitude

Pressure altitude (PA) and density altitude (DA) are disseminated locally.
Disseminate PA (e.g., PA +130) or DA (e.g., DA +3680) following the last element or remark in the observation, with the exception of runway condition remarks which are reported last.

Corrections to Transmitted Data

Disseminate corrections (COR) to transmitted data in the same manner as the observation being corrected as soon as possible whenever an error is detected in a transmitted report.
Use the original date and time of the observation as the date and time in the COR'd observation.

Observing and Reporting Standards for Pressure Measurements

All pressure values are initially derived from the atmospheric pressure as measured by a barometer and may be reported in either inches of mercury (iHg) or hectopascals (hPa).
Station pressure is defined as the atmospheric pressure computed for the level of the station elevation.

Altimeter Setting

The altimeter setting is a computed pressure value that an aircraft altimeter scale is set to so it indicates the altitude above MSL of an aircraft on the ground at the location for which the value was determined.
The letter "A" is used to identify an altimeter setting in observations at CONUS locations and OCONUS US military locations.

Sea-Level Pressure (SLP)

SLP is a report of the theoretical reduction of station pressure to sea level.
Where the earth's surface is above sea level, it is assumed the atmosphere extends to sea level below the observing location, and the properties of the hypothetical atmosphere are related to conditions observed at the unit.

Pressure Tendency

Pressure tendency is a coded report (5-group) included on the 3-hourly observations that indicates the characteristic and amount of pressure change during the 3-hour period preceding the observation.

Code Figure, Difference in Pressure (iHg and hPa)

Code figures are used to report differences in pressure in inches of mercury (iHg) and hectopascals (hPa).
The code figures are based on the conversion from inches of mercury to hectopascals since station pressure is taken in inches of mercury.

METAR and SPECI Reports

METAR and SPECI reports are used to provide weather information to aviation authorities
The type of report (METAR or SPECI) is included in all reports
SPECI reports are used when specific weather conditions are met, otherwise, METAR reports are used

Station Identifier (CCCC)

The observing location identifier, CCCC, is a four-alphanumeric character code
The identifier is typically representative of the airfield identifier according to the ICAO

Date and Time of Report (YYGGggZ)

The date and time of the report are included in all reports
The time is the actual time the report is transmitted or when the SPECI criteria are met
Time is reported in UTC (Coordinated Universal Time)

Wind Group (dddff(f)Gfmfm(fm)KT_dndndnVdxdxdx)

The wind group includes the direction, speed, and gusts of the wind
Wind direction is reported in tens of degrees using three figures (ddd)
Wind speed is reported in whole knots using the tens and units digits (ff(f))
Wind gusts are reported in knots, if applicable (Gfmfm(fm))

Visibility and Runway Visual Range

Visibility is reported in meters (VVVVVSM) or feet (VVVV)
Runway Visual Range is reported in meters (RDRDR[DR]//VRVRVRVRFT) or feet (RDRDR[DR]/VNVNVNVNVVXVXVXVXFT)

Present Weather and Sky Condition

Present weather is reported using a code (w'w')
Sky condition is reported using a code (NsNsNshshshs or VVhshshs or CLR)

Temperature and Dew Point

Temperature and dew point are reported in Celsius (T'T'/T'dT'd)

Altimeter and Remarks

Altimeter is reported in hectopascals (APHPHPHPH)
Remarks are used to provide additional information about the weather report

Unofficial Weather Reports

Unofficial weather reports are defined as reports from individuals who are not task-certified to take official weather observations
Unofficial reports can provide additional and supplemental information that may be important to local aviation and public safety

Modes of Observation

The point of observation is defined as the designated spot where the elements of an observation are viewed and/or sensed
The point of observation is within 5 SM (8000 m) of the airfield and affords as clear a view as possible of the runway complex

Automated and Manual Observations

Automated observations are made using primary and discontinuity sensor groups
Manual observations are made using augmented/weather personnel

Weather Certification and Position Qualification

Weather personnel are trained, task-certified, and position-qualified IAW applicable Career Field Education and Training Plan
Task-certification is required for weather personnel to evaluate tower visibility values from the control tower

Station Information File

The station information file is updated and maintained by weather personnel
The file includes information about the weather station, including location, elevation, and equipment

Accuracy of Time

The accuracy of the time ascribed to weather observations is of the utmost importance
The standard clock is a standalone clock zeroed with the US Naval Observatory time

Wind Measurement

Wind is measured in terms of velocity, a vector that includes direction and speed
Wind is measured in an unobstructed area to minimize inconsistencies caused by local obstructions

LOCALs and Dissemination

LOCALs are single element observations that contain time and ALSTG (altimeter setting)
When ATC does not have access to real-time ALSTGs, WFs/Dets will disseminate an ALSTG LOCAL observation at an interval not to exceed 35 minutes when there has been a change of 0.01 inches of mercury (iHg) or more since the last disseminated ALSTG value

METAR/SPECI Code Format

The METAR/SPECI report has two major sections: Body and Remarks
The Body contains:
- Type of report (METAR or SPECI)
- Station identifier (CCCC)
- Date and time of report (YYGGggZ)
- Report modifier (COR or AUTO)
- Wind (dddff(f)Gfmfm(fm)KT_dndndnVdxdxdx)
- Visibility (VVVVVSM or VVVV)
- Runway visual range (RDRDR[DR]//VRVRVRVRFT or RDRDR[DR]/VNVNVNVNVVXVXVXVXFT)
- Present weather (w'w')
- Sky condition (NsNsNshshshs or VVhshshs or CLR)
- Temperature and dew point (T'T'/T'dT'd)
- Altimeter (APHPHPHPH)
The Remarks section contains:
- Automated, manual, and plain language
- Additive and maintenance data

Coding METAR or SPECI Reports

Type of report (METAR or SPECI) is included in all reports
Station identifier (CCCC) is included in all reports
Date and time of report (YYGGggZ) is included in all reports
Report modifier (COR or AUTO) is included in all reports
COR is used for corrections to previously disseminated reports
AUTO identifies fully automated reports with no human intervention

Coding Missing Data in METAR and SPECI Reports

When an element does not occur or cannot be observed, the corresponding group and preceding space are omitted from the report
FBWOS automatically places a missing data flag (M) in the corresponding data field and includes the maintenance indicator ($) at the end of the observation when a sensor fails

Remarks (RMK)

Remarks are used to elaborate on parameters reported in the body of the report
Remarks are included in all METAR and SPECI observations if required

FBWOS and Sensor Siting

FBWOS sensors are sited in accordance with the Unified Facilities Criteria 3-260-1 (UFC 3-260-1), Airfield and Heliport Planning and Design
FBWOSs must be certified as conforming with station certification requirements contained in FCM-H1

Site Acceptance and Commissioning

Site acceptance and commissioning of FBWOS are accomplished by the host-installation AF weather organization or by the sponsoring MAJCOM, Lead Command, and the Program Managers Office

AN/TMQ-53s

AN/TMQ-53s are used for tactical airfields or as long-term backup for fixed meteorological sensors at AF and Army controlled airfields
AN/TMQ-53s are not used as standalone weather sensors outside the local aerodrome without prior approval from the parent MAJCOM

CONVECTIVE CLOUD-BASE HEIGHT TABLE

The table shows the estimated cloud-base height (in ft) based on surface dewpoint depression (°C)

Local Weather Observations

LOCALs are single element observations that contain the time and the observed element (e.g. altimeter setting, ALSTG).
ALSTG LOCALs are disseminated at an interval not to exceed 35 minutes when there has been a change of 0.01 inches of mercury (iHg) or more since the last disseminated ALSTG value.

METAR/SPECI Code Format

The METAR/SPECI report has two major sections: the Body and the Remarks.
The Body and Remarks sections are encoded in the order shown in Figure 3.1.
The actual content of the report depends on the observation program at the individual observing organization.

Automated/Augmented METAR/SPECI Code

Most WFs/Dets use an Automated Data System (ADS) as the primary local and longline dissemination system.
When the ADS is unavailable, use AF Weather-Web Service (AFW-WEBS), the OWS or another WF/Det to disseminate observations longline.

Pressure Altitude and Density Altitude

Pressure altitude (PA) and density altitude (DA) are disseminated locally.
PA and DA are disseminated following the last element or remark in the observation, with the exception of runway condition remarks which are reported last.

Corrections to Transmitted Data

Corrections (COR) to transmitted data are disseminated in the same manner as the observation being corrected as soon as possible whenever an error is detected in a transmitted report.
Transmitted corrections will consist of the entire corrected observation, using the original date and time of the observation.

Back-up and Manual Observations

Back-up is the process of manually editing/adding data or dissemination capability when the primary method is not operational, unavailable, or suspected to be providing erroneous data.
Back-up is required during controlled airfield hours and may be required during uncontrolled airfield hours when elements triggering weather warnings are erroneously reported and/or when required for supplementation criteria.
Weather personnel will not replace the entire automated observation with a manual observation when backing-up malfunctioning sensors, but will follow guidance in Attachment 2 and Attachment 3 and report the individual required elements.

Back-up Equipment

Use an available Air Force-certified system to back-up the primary certified observing systems (e.g., AN/FMQ-19 discontinuity sensors, AN/TMQ-53) or approved manual methods.
Manual observing equipment will be operated and maintained according to this manual and the applicable T.O. or user manual.

Sky Condition Reporting

Clear skies are encoded in the format, CLR or SKC, where CLR is the abbreviation used by all FBWOS locations and SKC is used by manual stations to indicate no clouds are present.
Each layer is separated from other layers by a space.
The sky cover for each layer reported is encoded by using the appropriate reportable contraction.
The abbreviations FEW, SCT, BKN, and OVC will be followed, without a space, by the height of the cloud layer.
A partial obscuration will be encoded with the reportable layer construction corresponding to the amount of the sky that is obscured followed by the layer height.

Altimeter Settings and Conversion

The table provides conversions between inches of mercury (iHg) and hectopascals (hPa) for altimeter settings.
The hPa values in the table are truncated to their reportable value (i.e. rounded down to the nearest whole hPa).

Exception

WFs/Dets will not use inactive/parallel runway equipment to back-up a faulty RVR reading
Encode RVRNO as part of the official observation (may still encode a supplemental RVR reading)

Observation Augmentation

Augmentation is the process of having position-qualified weather personnel edit or add additional data to an observation generated by an FBWOS
Two augmentation processes: supplement and back-up
Weather personnel must have a view of the airfield complex and maintain situational awareness of the current conditions as well as the FBWOS-sensed data and observations

Supplementing FBWOSs

Supplementing is the process of manually adding observed weather conditions beyond the capabilities of the FBWOS to detect and/or report to an observation
Weather personnel will supplement observations during controlled airfield hours and check the weather at intervals not to exceed 20 minutes whenever mandatory supplemental criteria are observed or forecast to occur within 1 hour
Mandatory supplementation conditions:
- Tornado (+FC)
- Waterspout (+FC)
- Funnel Cloud (FC)
- Freezing Precipitation (FZDZ/FZRA)
- Ice Pellets (PL)
- Hail (GR)
- Sandstorm (SS)/Dust Storm (DS)
- Volcanic Ash (VA)
- Tower Visibility remark

Back-up

Back-up process uses different encoding for wind speed, direction, and gusts
Wind algorithms use 5-second average wind directions and speeds to compute and report the 2-minute average in the observation
Wind direction is determined by averaging the direction the wind is coming from with regards to true north, over a 2-minute period

Wind Reporting

Wind element reporting characteristics:
- Wind direction
- Wind speed
- Wind gusts
- Wind shifts
- Peak wind data
Wind encoding formats:
- Wind speed (e.g., 08KT, 112KT)
- Wind gusts (e.g., Gfmfm(fm))
- Variable wind direction (e.g., VRB03KT, 21010KT 180V240)
- Calm wind (e.g., 00000KT)

Pressure and Altitude

Pressure altitude (PA) and density altitude (DA) are automatically computed by FBWOSs and displayed on the ADS (e.g., JET) and TMQ-53 sensor displays
PA and DA can also be computed using the OWS or AFW-WEBS Forecaster Tools
FBWOS and JET software compute DA using different formulas; the formula used by JET takes into account water vapor and the FBWOS does not
Rapid pressure changes are automatically detected by the FBWOS/JET and reported in the remarks of the observation using a specific format

SPECI Reports

A SPECI is an unscheduled observation that contains all data elements found in a METAR plus additional remarks.
SPECI reports are prepared and transmitted as soon as possible after the relevant criteria are observed.
The time ascribed to a SPECI reflects the time, to the nearest minute, that the SPECI criteria are first met or observed.

Base SPECI Criteria

Base SPECI criteria on published take-off, landing, and circling airfield minima.
Criteria may be supplemented with values from Combatant Commander Instructions, manuals, or supplements relating to minima for take-off, landing, VFR, IFR, and alternates.

LOCAL Reports

A LOCAL is an unscheduled observation, reported to the nearest minute, not meeting SPECI criteria.
LOCALs are only taken when unit leadership determines there is a requirement in support of local operations.
LOCALs taken in support of aircraft operations are encoded in METAR format.

Visibility Measurements

Use caution when using an object located in front of a terrestrial background, as the object may be located closer to the point of observation than it is to the terrestrial background.
The most suitable nighttime visibility markers are unfocused lights of moderate intensity.
Control Tower Visibility Aids require control towers to maintain a visibility checkpoint chart or list of visibility markers posted in the tower.

Aircraft Mishap

Upon notification of an aircraft mishap, WFs/Dets will immediately encode and disseminate a full element SPECI.
A SPECI is not required for an in-flight emergency (IFE), but weather personnel should be prepared to take a SPECI if the IFE becomes a mishap.

Inactive/Parallel Runway Equipment

Supplemental data may be requested by ATC to control aircraft using an inactive runway.
WFs/Dets will not use inactive/parallel runway equipment to back-up a faulty RVR reading.

Observation Augmentation

Augmentation is the process of having position-qualified weather personnel edit or add additional data to an observation generated by an FBWOS.
Weather personnel must have a view of the airfield complex and maintain situational awareness of the current conditions as well as the FBWOS-sensed data and observations.

Supplementing FBWOSs

Supplementing is the process of manually adding observed weather conditions beyond the capabilities of the FBWOS to detect and/or report to an observation.
Weather personnel will supplement observations during controlled airfield hours and check the weather at intervals not to exceed 20 minutes whenever mandatory supplemental criteria are observed or forecast to occur within 1 hour.

Mandatory Supplementation Conditions

Tornado, waterspout, funnel cloud, freezing precipitation, ice pellets, hail, sandstorm, dust storm, and volcanic ash.
Tower visibility remark is only required during controlled airfield hours.

Back-up

Back-up is a general description of atmospheric pressure characterization.
Pressure characterization codes are used to describe the pressure change in the last 3 hours.

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Questions and Answers

What is the federal standard for siting meteorological sensors at airports, as mentioned in the content?

What is the maximum duration for short-term sensor outages before alternative methods are used?

What happens when weather personnel log out malfunctioning equipment?

What can be used to obtain values during short-term sensor outages?

What is a sufficient reason to consider the prevailing visibility the same as at the control tower level?

Why are deficiency reports created for false readings on specific sensors?

When should a tower visibility remark be included in the next METAR or SPECI?

What is the temperature range for evaluating the risk of freezing precipitation?

What type of photographs are recommended for visibility reference tools?

What happens when the risk of freezing precipitation is low?

What should be clearly identified in objects in the visibility reference tool?

What is the reference for additional information on equipment inventory, status, and utilization reporting?

What is highly recommended for the visibility reference tool?

What can be used to determine marker distances while creating/updating visibility reference tools?

What are the most suitable daytime markers?

What can WFs/Dets submit to survey the markers through if needed?

What is the unit of measurement used for station pressure and altimeter settings in the United States and at US military organizations overseas?

What is the range of pressure measurement that FBWOS sensors are capable of?

How often are pressure computations made by FBWOS?

What is the significance of the four-digit group immediately following the A in the altimeter encoding?

What happens to pressure values when they are reported?

What type of pressure values are considered estimated when the readings are suspect or obtained through any method other than the primary sensor?

Under what conditions can the AN/TMQ-53 be used as a back-up without estimating pressure values?

What is the primary measurement of atmospheric pressure used in observations?

What is the primary method for determining Pressure Altitude (PA) and Density Altitude (DA)?

What is the difference between the formula used by JET and FBWOS to compute DA?

When is it necessary to notify ATC agencies that the reported PA and DA values are estimated?

What is the purpose of a barometer comparison/calibration program?

When should comparisons be delayed during barometer calibration?

What is the format for reporting rapid pressure changes in the remarks of the observation?

What is the purpose of recording and documenting barometer comparisons?

What is the recommended frequency for establishing a barometer comparison/calibration program?

What is the purpose of a METAR/SPECI observation?

What does the abbreviation 'AO2' stand for?

What is the purpose of a DAF Form 679?

What does the abbreviation 'CBMAM' stand for?

What is the purpose of a UFC 3-260-01?

What does the abbreviation 'COR' stand for?

What is the purpose of a JET Form 3818?

What does the abbreviation 'CIG' stand for?

What should be entered in column 13 of AF Form 3803/JET Form 3813 when an augmented observation is not able to be transmitted longline before the next METAR or SPECI is required?

What should be done when a SPECI is not transmitted longline?

How should reports of a volcanic eruption be disseminated?

What is the purpose of FBWOSs?

What should be included in a METAR when a later observation containing all elements of a METAR is available for transmission?

How should longline dissemination by another WF/Det be recorded?

What is the primary purpose of Chapter 4 of AFMAN15-111?

What type of equipment operates in automated mode at AF and Army controlled airfields?

What should you do when determining wind direction manually using a compass?

Which of the following can be used to determine wind speed manually if an anemometer is not available?

What is the purpose of the Beaufort scale?

When determining wind speed manually, where should the anemometer be held?

What is the significance of Table 11.2?

What is the lowest priority layer for reporting according to Table 11.2?

Which of the following is not a method for determining wind speed?

What should you avoid using when determining wind direction?

What is the lowest height that FBWOSs can report sky condition from?

How are heights of layers reported in METAR and SPECI observations?

What is the sky cover at any level determined by?

What is the minimum amount of sky that a surface-based obscuring phenomenon must cover to be classified as a layer?

How are layer heights between 5,000ft and 10,000ft reported?

What happens when a layer height value falls halfway between two reportable increments?

What is the maximum height that FBWOSs can report sky condition up to?

How are clouds and/or obscuring phenomena with bases at approximately the same level classified?

What code figure would be assigned to an atmospheric pressure that is decreasing, then increasing?

What does a code figure of '4' indicate about atmospheric pressure?

What code figure would be assigned to an atmospheric pressure that is increasing, then decreasing?

What does a code figure of '7' indicate about atmospheric pressure?

What code figure would be assigned to an atmospheric pressure that is decreasing, then steady, or decreasing then decreasing more slowly?

What does a code figure of '3' indicate about atmospheric pressure?

What is the atmospheric pressure computed for the level of the station elevation?

What code figure would be assigned to an atmospheric pressure that is steady or increasing, then decreasing; or decreasing then decreasing more rapidly?

What code figure would be assigned to an atmospheric pressure that is increasing steadily or unsteadily?

What is the purpose of the altimeter setting?

What is the international community's acronym for station pressure?

What is the report of the theoretical reduction of station pressure to sea level?