FRONTSWHERE TWO AIR MASSES MEET, BUT DO NOT MIX

COLD FRONT

COLD FRONT• Cold air “crashes” into warm air causing the

warm air to rise quickly.• Water Vapor rises quickly, cools condenses

and creates clouds.• Frequently creates cumulonimbus clouds

which cause severe weather (thunderstorms or even tornadoes)

• Quickly moving front

COLD FRONTSYMBOL ON A WEATHER MAP

WARM FRONT

WARM FRONT• Warm air “slowly creeps” over cold air causing

the warm air to rise slowly.• Water Vapor rises slowly, cools condenses and

creates clouds.• Frequently creates stratus or nimbostratus

clouds which cause longer periods of rain or snow.

• Slowly moving front

WARM FRONTSYMBOL ON A WEATHER MAP

STATIONARY FRONT

STATIONARY FRONT• Similar air masses “sit next to each other”

because neither is “strong enough” to rise over or push under the other.

• Water Vapor rises very slowly, cools condenses and creates clouds.

• Frequently creates stratus or nimbostratus clouds which cause very long periods of light rain or snow.

• Very slow moving front

STATIONARY FRONTSYMBOL ON A WEATHER MAP

OCCLUDED FRONT

OCCLUDED FRONT• Starts as a cold front and warm front. The cold

air forces the warm air away from the surface.• Water Vapor rises, cools condenses and creates

clouds.• Depending on the speed that the warm air rises,

it can create stratus or nimbostratus clouds or cumulonimbus clouds.

• Most complex type of front because it involves 3 different air masses.

OCCLUDED FRONTSYMBOL ON A WEATHER MAP