Download - Fronts & Storms
Fronts & Storms
by Mrs. Wisher
WRITE EVERYTHING IN GREEN
Air Masses
• air mass – a huge body of air that has similar temperature, humidity, and air pressure throughout
• maritime air masses forms over oceans• continental air masses form over land• polar air masses form in cold regions and
tropical air masses form in warm areas
Fronts
• Fronts occur when 2 air masses meet but do not mix
• When fronts combine they often cause storms or changes in weather
Cold Fronts
• cold fronts – when a fast moving cold air mass runs into a slow moving war air mass, the cold dense air slides underneath
• cold fronts cause cloudy skies with possible heavy rain or thunderstorms & colder temperatures
Warm Fronts
• a moving warm air mass collides with a slow moving cold air mass
• weather can be humid or dry but will be warmer
warm air
cold air
Stationary Fronts
• When a cold and warm air mass meet but do not have the force to move each other
• Weather can be cloudy or rainy for an extended period of time.
Occluded Front
• Occurs when a warm air mass is trapped between 2 cold air masses
• This pushes the warm air mass upwards and the temperature cools
Storms
• storm – a violent disturbance in the atmosphere • usually cause changes in air pressure
Thunderstorms• Thunderstorms form within large cumulonimbus cloud• lightning – a sudden energy discharge from a cloud to another cloud
or the ground• thunder – the sound produced by the rapid heating of the air after a
lightning strike
Tornados
• Tornados are funnel shaped clouds with rotating speeds of up to 480 km per hour
• They form in the same cumulonimbus clouds as thunderstorms
• Most tornados form in the Great Plains which is known as Tornado Alley.
tornado images
Hurricanes
• A tropical storm with winds higher than 119 km per hour
• Hurricanes begin over warm water as a tropical disturbance
Blizzard
• A snowstorm with high speed sustained winds.
• Wind speeds over 35 miles per hour and lasts at least 3 hours.
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