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A huge body of air that has similar temperature, humidity, and air pressure at any given height.
A cold air mass that forms north of 50 degrees north latitude or south of 50 degrees south latitude and has high air pressure.
cold air is dense and sinks, warm air is less dense and rises; the denser cold air slides under the lighter warm air; brings clouds and heavy precipitation
A warm air mass is caught between two cooler air masses; brings clouds and precipitation
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