{Weather Fronts

Polar air masses are going to be represented with a capital "P" Tropical air masses are going to be represented with a capital

"T" "Maritime" will be represented with a lower case "m" in front of

the P or T "Continental" will be represented with a lower case "c" in front

of the P or T

Air Mass Labeling

cP: cold, dry cT: hot, dry mP: cool, humid mT: warm, humid

Air Mass Characteristics?

Fronts are large boundaries that separate different air masses, one warmer and often having a higher moisture content than the other.

Frontin'

Generally, an air mass on one side of the front is going to move faster relative to the front boundary than the other air mass on the other side.

Therefore, one air mass is always advancing on another

Front Movement

Not that much mixing of the air masses

Basically retain their distinct identities as one goes over the other in a process called overrunning

The Front

No matter what, it is always warmer (LESS DENSE) air that is forced on top

Marked by red semi-circles with the rounded edge pointing in the direction of the front

When a front moves so that warm air is occupying a space that was formally occupied by cold air it is called a warm front

Advances slooooowwwwlyyyyy, 10-15 mph

Warm Fronts

The weather for a warm front can stretch out a 1000 miles ahead of it and can start appearing 36 to 48 hours ahead of it

Weather starts out as thin, wispy cirrus clouds (halo around sun/moon)

With time, these thin clouds get gradually lower and thicken

Eventually there's a steady light rain or drizzle Near the actual frontal boundary, precipitation

tends to become steadier and heavier and there could also be areas of fog as well

Could last for days

Warm Fronts

When cold, dense air is actively advancing into an area occupied by warmer air

These fronts are twice as steep and 50% faster than warm fronts, going at about 20-25 mph

Like an atmospheric plow Represented by blue triangles, like spikes,

in the direction that the front is moving

Cold Fronts

Weather along these fronts are much more violent

Creates: Towering cumulus clouds Hard showers Gusty thunderstorms

All of this is followed by a push of colder, drier air

Cold Fronts

When a cold front over takes a warm front forcing it up

Then this cold air bumps up against another cold front

2 Types: In a cold occlusion, the air mass

overtaking the warm front is cooler than the cool air ahead of the warm front, and plows under both air masses.

In a warm occlusion, the air mass overtaking the warm front is not as cool as the cold air ahead of the warm front, and rides over the colder air mass while lifting the warm air.

Occluded Front

INTENSE weather Storm systems reach their greatest

intensity when they become "occluded" (when the cold meets the cold and forces the warm up)

Brings heavy rain, gusty winds, and thunderstorms

Eventually dies down when air mixes Marked by purple alternating semi-circles

and triangles pointing in the direction of the front

Occluded Front Weather

No significant movement and neither air mass is overtaking the other

The resultant weather is usually low cloud cover and long duration precipitation. Not too much wind.

Marked by red semi-circles and blue triangles pointing in opposite directions

Stationary Front