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WeatherWeather

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The general name for a large body of air having uniform temperature and moisture content is called an air mass.

During the summer continental tropical air masses flow over North America.

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There are 4 types of air massesThere are 4 types of air masses

Continental Polar (cP) form over land that is Continental Polar (cP) form over land that is covered by ice and snow. They bring cool covered by ice and snow. They bring cool or cold weather but it is usually dry.or cold weather but it is usually dry.

Continental Tropical (cT) form over deserts Continental Tropical (cT) form over deserts and usually bring clear, dry, and hot and usually bring clear, dry, and hot weather.weather.

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Maritime Polar (mP) form over the Northern Maritime Polar (mP) form over the Northern and Southern Oceans with cool water. They and Southern Oceans with cool water. They usually bring snow in the winter.usually bring snow in the winter.

Maritime Tropical (mT) form over warm Maritime Tropical (mT) form over warm waters of the oceans. They usually bring waters of the oceans. They usually bring heavy rain and thunderstorms.heavy rain and thunderstorms.

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Lightning causes a rapid expansion and collapse of the air that produces thunder.

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Cold fronts are shown withCold fronts are shown with

only trianglesonly triangles Warm fronts are shown Warm fronts are shown

With only half circlesWith only half circles Occluded fronts have alternating triangles Occluded fronts have alternating triangles

and half circles on the same sideand half circles on the same side Stationary fronts have alternating triangles Stationary fronts have alternating triangles

and half circles on opposite sidesand half circles on opposite sides

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During the summers, air masses that form over the southwestern United States usually bring weather that is hot and clear.

Warm fronts generally have a gradual slope and produce heavy precipitation over large areas.

Warm fronts form when a warm air mass overtakes a cold air mass.

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Tornados are short lived storms that have the highest wind speeds of any storm

Hurricanes are the largest storms that have the most energy of any storm

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Wind vanes measures wind direction. Satellite images made using infrared energy

primarily reveal information about atmospheric temperatures

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A liquid thermometer is shown in this diagram.

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Satellites carry mounted cameras designed to photograph the tops of clouds in the uppermost layers of the atmosphere.

A barometer is used to measure air pressure.

Thermographs are used to measure temperature changes.