Sleet happens when snow hits a warmer layer of the atmosphere, turns to rain, but then passes back into a freezing level of the atmosphere. That rain will re-freeze into small ice pellets known as sleet. So basically, freezing rain equals a coating of ice, and sleet means scattered pellets of ice.

The National Weather Service defines a "wintry mix" as precipitation that could include snow, sleet, freezing rain or some combination of all three at different times. The form of precipitation that forms depends on varying temperatures in the atmosphere,