Many times I hear people say during a winter storm that it is hailing. This is actually called sleet. Hail normally occurs in thunderstorms and is the result of strong updrafts that repeatedly carry growing chunks of ice upwards into the clouds. Once the hail stones become too heavy to be lifted by the updrafts, they fall to the ground. Hail stones are normally much larger than sleet pellets and they can cause damage to crops, windshields, people, etc. Sleet occurs during a winter storm and is caused by rain falling into a cold layer of air aloft which has to be below freezing. As the raindrops fall through the cold layer of air, they freeze and become small ice pellets. When they hit your car windshield or your windows at home, they can make quite a racket. Sleet can accumulate on the roads and sidewalks making driving and walking quite hazardous. Freezing rain is basically rain that falls onto the ground and then freezes AFTER it hits the ground. It causes a glaze of ice on trees and any surface that is below freezing. Freezing rain causes the most hazardous of driving and walking conditions. Freezing rain is what causes the power outages as a result of the ice that forms on the trees and power lines making them so heavy that they come down. A temperature inversion causes the conditions that result in freezing rain. This means that it is warmer aloft than it is at the surface
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