Questions and Answers
If wind direction must be estimated, which of the following aids can be used? (Select all that apply)
How would moderate snow and blowing snow be encoded?
SN BLSN
How would heavy rain and light drizzle be encoded?
+RADZ
How would shallow fog be encoded?
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Non-surfaced based layers are encoded in hundreds of feet ____ using 3 digits.
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What is the reportable prevailing visibility when visibility values vary between 2, 3, and 4 statute miles?
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Sector visibility is encoded in column ____ of the MF1M-10C.
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What is the definition of multiple layers?
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What wind speed is required to define a wind shift?
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How would a temperature of 10 and a missing dew point be encoded for transmission in an observation?
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How would thunderstorms southeast through southwest of the observation location be encoded?
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What would be the best way to encode a thunderstorm that began at 1515z and ended at 1534z in an observation?
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What is the first step to determining the altimeter when using a mercurial barometer?
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How would a thunderstorm that began at 0307z and ended at 0328z be encoded?
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How would frequent lightning from cloud-to-ground and cloud to air in the vicinity of the observation location be encoded?
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What type of observation is required when a wind shift occurs?
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What instrument is used to measure temperature?
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How would an altimeter reading of 29.95 inches of mercury be encoded?
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What type of writing instrument should an observer use when filling out the MF1M-10C?
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How would a moderate dust storm be encoded for transmission in an observation?
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How would heavy freezing drizzle be encoded for transmission in an observation?
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If you determined the observed prevailing visibility to be 2 7/8sm, what visibility would be reported on the MF1M-10C?
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When the visibility is not the same around the horizon circle, it is said to be ____.
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How would the wind speed of 20 knots be encoded in column 4?
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Tower visibility observations must be taken when reported surface and/or tower prevailing visibility is less than ____ statute miles.
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Temperature is the degree of ____ of the ambient air as measured by any suitable instrument.
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Sector visibility follows ____ visibility in the remarks section.
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What is the definition of hail (GR)?
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Which of the following is not used to measure pressure?
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How would frequent lightning from cloud-to-ground and cloud to air in the vicinity of the observation location be encoded?
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How is a cumulonimbus cloud located to the north of the observation location and moving south encoded?
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What contraction is used to denote 5/8 to 7/8 of sky covered by clouds?
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What is the definition of snow (SN)?
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What is the latest time that a METAR observation can occur?
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Study Notes
Weather Observation Encoding
- Wind direction aids include wind cones, leaves, and smoke for estimation.
- Moderate snow and blowing snow encoded as SN BLSN.
- Heavy rain is encoded as +RADZ, while light drizzle is denoted as RADZ.
- Shallow fog is represented by MIFG.
- Non-surface based layers are encoded in hundreds of feet above ground using 3-digit numbers.
Visibility Reporting
- Prevailing visibility determined from varying values (e.g., 2, 3, 4 statute miles) is reported as 3sm.
- Sector visibility encoded in column 14 of the MF1M-10C.
- Non-uniform visibility indicates inconsistency around the horizon.
- Tower visibility is reported when surface visibility is less than 4 statute miles.
Weather Conditions and Intensity
- Wind shifts defined as a change of 45 degrees or more within 15 minutes at sustained speeds of 10 knots or more.
- Reporting tornadoes requires the contraction +FC, whereas smoke is denoted as FU.
- Heavy freezing drizzle encoded as +FZDZ, and moderate dust storms as DS.
Special Observations
- Special observations are required when significant changes occur, such as a ceiling less than 1,000 feet or visibility below certain thresholds.
- Light freezing rain ending warrants a special observation due to its implications on safety.
Cloud and Sky Cover
- Towering cumulus and cumulonimbus cloud types can be reported with sky cover information.
- Sky coverage denoted as BKN corresponds to 5/8 to 7/8 of the sky covered.
- Clear skies are indicated with SKC, while high cloud cover is signified by specific terms like FEW, SCT, and BKN.
Temperature and Pressure Encoding
- Temperature readings are encoded in two-digit format, e.g., 10°C as 10/ and 4.3°C as 04.
- Altimeter readings in inches of mercury are encoded without a decimal, e.g., 29.95 inches as 2995.
Lightning Conditions
- Frequency of lightning is categorized, with continuous lightning requiring more than 6 flashes per minute.
- Lightning within 5 statute miles of the observation is represented by OHD.
General Measurement Notes
- Wind speed and gusts are measured to the nearest whole knot with gusts recorded when variations exceed 10 knots.
- Visibility for the body of reports is determined by the lower value between surface and tower observation.
Observational Methods
- Special observations must be encoded as S in column 1 of the MF1M-10C when significant weather changes occur.
- Three present weather groups can be encoded in column 9, with variable visibility following the main visibility report in remarks.
Additional Definitions
- Dew point temperature measures atmospheric moisture.
- Total obscuration signifies complete blockage (8/8) due to surface-based obstructions.
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Description
This quiz consists of flashcards designed to help you study the LAWRS (Low Altitude Weather Reporting System) definitions and encodings. Each card features specific weather conditions and their respective codes, aiding in the comprehension of meteorological terms and encoding. Perfect for students and professionals seeking to enhance their understanding of weather reporting.
