COPY: Weather Fronts Quiz

Understanding Weather Fronts

• A weather front is a boundary separating air masses of different densities, wind, temperature, and humidity.
• Cold fronts generally move from west to east, whereas warm fronts move poleward, although any direction is possible.
• Occluded fronts are a hybrid merge of the two, and stationary fronts are stalled in their motion.
• A surface weather analysis provides a top view of weather elements over a geographical area at a specified time based on information from ground-based weather stations.
• Cold fronts often bring rain, and sometimes heavy thunderstorms as well. Cold fronts can produce sharper and more intense changes in weather and move at a rate that is up to twice as fast as warm fronts.
• Warm fronts are at the leading edge of a homogeneous advancing warm air mass, which is located on the equatorward edge of the gradient in isotherms, and lie within broader troughs of low pressure than cold fronts.
• An occluded front is formed when a cold front overtakes a warm front, and usually forms around mature low-pressure areas, including cyclones.
• A stationary front is a non-moving (or stalled) boundary between two air masses, neither of which is strong enough to replace the other.
• A similar phenomenon to a weather front is the dry line, which is the boundary between air masses with significant moisture differences instead of temperature.
• Organized areas of thunderstorm activity not only reinforce pre-existing frontal zones, but can outrun actively existing cold fronts in a pattern where the upper level jet splits apart into two streams.
• Fronts are the principal cause of significant weather. Convective precipitation is caused by air being lifted and condensing into clouds by the movement of the cold front or cold occlusion under a mass of warmer, moist air.
• Fronts are generally guided by winds aloft, but do not move as quickly.