Download 22.5 Weather Patterns

Chapter 24.5
Weather Patterns
•Air Masses:
- large body of air
that forms over an area
of the Earth’s surface.
Continental
Polar
Maritime
Tropical
Fronts
• The boundary where 2
unlike air masses meet.
Cold
Warm
Stationary
Occluded
Cold Front
warm air mass cold front
cold air mass
Cold Front
Weatherstrong winds, severe
thunderstorms, heavy
rain, tornadoes
Warm Front
Warm air mass
warm front
Cold air mass
Warm Front
Weather –
steady rain then clear
skies with warmer temps.
Stationary Front
Stationary Front
Weather –
clouds, steady rain or
snow for several days
Occluded Front
cold air mass warm air mass
cold air mass
Occluded Front
Weather –
cloudy skies and
precipitation
Weather Systems
• High Pressure – air flows down and
away – fair weather (anticyclone-winds
blow clockwise)
• Low Pressure – air flows up and to
center – storms, tornadoes, hurricanes
(Cyclone-winds blow counterclockwise
and with jet stream
Storms
•Thunderstorms-air
rises within
cumulonimbus cloud.
Small, thunder &
lightning, winds, hail
Tornadoes
• Vertical cylinder of rotating air
develops in a thunderstorm.
Usually about 120mph
-Very low pressure
-Form on the leading edge
of a cold front.
-Cyclones of middle latitudes
Hurricanes
• Large tropical cyclone with
sustained winds of at least
75mph
(< 75 is a tropical storm)
• Form over warm water in
tropics