Air Masses & Fronts

Weather is caused by the movement & interaction of air masses

Each Mass is described with a Temperature & Moisture

Ex: Hot / Dry Ex: Cold / Moist

Air Mass- large body of air that has properties similar to the part of the Earth’s surface over which it develops

Air mass that forms over tropics is _______ than one that forms over the northern regions.

Air mass that forms over water is more ______ than one that forms over dry land.

Characteristics of Air

Recall: Winds blow from an area of ______ pressure to an area of _____ pressure!

(high to low)

Highs & Lows

Associated with fair / nice weather because the high pressure does not allow air to rise and form clouds

Hint: Think of High 5= Good Weather Or Thumbs UP!

HIGH PRESSURE SYSTEM

Associated with cloudy weather because the warm air rises and forms clouds

Thumbs Down

LOW PRESSURE SYSTEM

It is usually cloudy and stormy at a front

4 Types◦ Cold◦ Warm◦ Occluded◦ Stationary

Fronts- boundary that forms between 2 different air masses

Familiar FrontsIn your journals, identify these symbols

Divide your paper into four equal sections Read the FRONTS section on page 127 &

128 Label each section with the 4 fronts:

◦ Cold Front, Warm Front, Occluded Front, Stationary Front

Describe what happens at each front & what type of weather occurs

Draw a picture of each front & use Red & Blue colored pencils to add color.

INCLUDE THE SYMBOL OF THE FRONT!!!!!!

Front Drawings

Cold Front

Fronts move in the direction they are headed!

Tips: The blue triangles on a cold front= think of icicle

Q: What types of temperatures are left after a cold front moves through?

Q: What direction is this cold front moving?

Cold Fronts Continued

Warm Front

Hint: The half circles on a warm front= think of the sun

Q: What types of temperature are left after a warm front moves through?

Q: What direction is this warm front moving?

Warm Fronts Continued…

Stationary Front Neither cold nor warm

air advances.

Hint: Think of the line of scrimmage in a football game when both teams equally push against each other

OR a Stationary Bike!

Occluded Front

Hint: The 2 C’s in oCCluded for 2 cold air masses.

Cold air masses close out the warm air from the surface.

The only front that includes ____ air masses. ( How many air masses are involved?)

Occluded Front Continued…