Fronts

Boundaries between air masses are called FRONTS. Near fronts the weather can be very unsettled, with rain and clouds. Some fronts cause lines of violent storms, as long as 500 miles!! The types of fronts that meteorologists tell us about are: Cold, Warm, Stationary, and Occluded.

This is the symbol that meteorologists use on weather maps for COLD FRONTS:
A cold front is a boundary between two different air masses where cold air pushes warm air away. It usually means colder weather. Cold fronts usually advance at speeds of about 20 mph- they are faster in the winter than in the summer, because in winter the air is colder and exerts greater pressure.


This is the symbol that meteorologists use on weather maps for WARM FRONTS:
A warm front is a boundary between two different air masses where warm air pushes cold air away to bring warmer weather. Warm fronts advance horizontally at speeds of about 15 mph or slower. Warm front weather extends over an area hundreds of miles in advance of the front line at ground level.


This is the symbol that meteorologists use on weather maps for STATIONARY FRONTS:
A stationary front is a boundary between a warm air mass and a cold air mass when no movement occurs. This type of front brings long periods of precipitation.


This is the symbol that meteorologists use on weather maps for OCCLUDED FRONTS:
An occluded front is a boundary on which a warm front has been overtaken by a cold front. It moves eastward and brings precipitation as well.