WHAT IS AN AIR MASS? HOW DO AIR MASSES FORM? WHAT IS FRONT? WHAT ARE THE FOUR TYPES OF FRONT?

1. Air masses
and
Fronts

2. Air Masses
It is a large body of air that
has fairly uniform physical
properties.

3. Characteristics of
Air Mass
1. Air mass must be large in size
2. Air mass must have a uniform
and consistent makeup at all
points within the air mass.
3. Air mass must be physically
bound together, traveling across
the atmosphere as a single unit.

4. HOW DO AIR MASSES
FORM?
It forms when a large body of air
becomes fairly stationary over a
region of Earth’s surface or as air
moves over a large, uniform region
like an ocean.

5. MaritimePolar
Arctic
ContinentalPolar
ContinentalTropical
MaritimeTropical

6. CLASSIFICATION OF
AIR MASSES
1. MARITIME AIR MASS - forms over water
2. CONTINENTAL AIR MASS – forms over land
3. POLAR AIR MASS – forms North of 50º or
South of 50º, where it is often extremely
cold.
4. TROPICAL AIR MASS – originates in the
tropics, where it is warm.

7. AIR MASSES THAT MOST AFFECT
WEATHER
• MARITIME POLAR – air masses originate over
frigid North Pacific and North Atlantic Ocean,
where are cool and moist, and often bring
heavy precipitation to coastal areas.
• CONTINENTAL POLAR – bring cold and dry
air .
• MARITIME TROPICAL – bring warm, moist air
and are often accompanied by fog or rain.
• CONTINENTAL TROPICAL – bring hot, dry air.

8. FRONTS
The sharply
defined
boundary that
forms when
two unlike air
masses meet.

9. TYPES OF FRONTS

10. Stationary front
• When two unlike air
masses have
formed a boundary
but neither is
moving front.
• Often result in
clouds and steady
rain or snow for
several days.

11. COLD FRONT
Occurs when a cold air
mass overtakes a warm
air mass.
cumulus and
cumulonimbus clouds
Strong winds, severe
thunderstorms and hail.

12. Warm Front
Occurs when a
warm air mass
overtakes a cold
air mass.
Steady rain,
heavy showers
or
thunderstorms.

13. OCCLUDED FRONT
when a warm air
mass is caught
between two cooler
air masses.

14. 1. HOW DO CLOUDS
FORM?
2. WHATARE THE MAJOR
TYPES OF CLOUDS?
ASSIGNMENT: