Transcript Air Masses and Fronts - ISD 186 | Pequot Lakes Schools

Air Masses and Fronts
Meteorology
Air Masses
• Classified by temperature and humidity
– Tropical: Warm, form in tropics, low pressure
– Polar: cold, form near poles, high pressure
– Maritime: form over oceans, humid
– Continental: form over land, dry
Fronts
• Colliding air masses
Cold fronts
• Cold air “undercuts” warm air. Front
moves quickly. If the warmer air mass
contains enough moisture, possible
storms, clouds, rain (vertically developing
clouds) followed by clear, cool weather.
Warm fronts
• Warm air “over-rides” cool air. Front
moves slowly. If the warmer air mass
contains enough moisture, clouds (stratus)
and rain may occur for several days
followed by warmer, more humid weather.
Stationary Fronts
• Neither air mass has enough force to
move the other. Weather depends on
moisture content of air masses.
Occluded Fronts
• Most complex front. Involves three air
masses: cool, cold, warm.