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Sleet

Breaking it Down with Brittney, Scientific Explainer.
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BREAKING IT DOWN WITH BRITTNEY - WINTRY MIX: Both freezing rain and sleet occur by the same general process: raindrops initially fall from the cloud in a layer of warm air, which is well above the ground. As these raindrops fall into a layer of freezing air that's hugging the ground... The difference between these two wintry precipitation types depends on the thickness of the layer of freezing air.

Freezing rain occurs when the layer of freezing air is so thin that the raindrops do not have enough time to freeze before reaching the ground. Instead, the water freezes on contact with the surface, creating a coating of ice on whatever the raindrops contact.

Sleet is simply frozen raindrops and occurs when the layer of freezing air along the surface is thicker. This causes the raindrops to freeze before reaching the ground.

Both of these pose threats for drivers. Ice creates slick spots on roadways, causing motorists to lose control of their automobiles with little to no warning. Bridges, overpasses and elevated roadways are especially susceptible to icing as they are surrounded on all sides by the cold air and freeze QUICKER. Remember to never get out of the car if you get into an accident. It's safer to wait inside the car until help arrives.

Ice caused by freezing rain can also rapidly add weight to tree branches and power lines, causing them to snap or break, leading to possible power outages.

Ice accumulation from freezing rain does not coat the surface of objects evenly. Gravity will usually cause the rainwater to run to the underside of an object before it freezes. Wind can create the same effect. In either case, the result would be a thicker coating of ice on one side of the object compared to the opposite side.