sually moves in large bodies called air masses. Some air masses move in from the north. These air masses usually have colder air that causes the temperature to drop. Air masses also movein from the south. They usually have warmer air that causes the temperature to rise.Temperature changes during the day or night can be great or small. This depends partly on how many clouds are in the sky. When there are many clouds during the night, they act like the covers on your bed. They blanket the earth and keep the air from losing much of its heat. The temperature usually does not drop much during such the night. When there are many clouds during the day, some of the sun’s energy will not reach the earth and the temperature usually does not rise much on such a day.
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