What does sleet mean?

Sleet refers to the weather phenomenon that rain and snow fall at the same time, or semi-melted snow.

Sleet (English: rain and snow mixing, sleet refers to a special precipitation phenomenon formed by mixing rain with partially melted snow and falling at the same time.

Unlike hail and freezing rain, sleet is relatively low in hardness and more transparent, but there are some traces of ice crystals, which are re-condensed by some melted snowflakes. In any place, the occurrence process of this weather phenomenon is relatively short, often in the stage from rain to snow, or the opposite stage.

"Winter shower": an informal meteorological term, first used in Britain, which refers to a mixture of rain, graupel and snow. Although there is no official standard for this term, in Britain, this term will not be used when there is obvious snow on the ground. Generally, it will be used when the ground temperature is higher than 0℃, the atmospheric temperature is lower than 0℃, and the ground temperature prevents snow on the ground and produces other substances.

Formation of hail

Sleet refers to semi-melted snow or rain and snow falling at the same time. The special condensation phenomenon of sleet requires temperature, which mainly occurs when the temperature of the part closest to the ground is slightly higher than the freezing point of water (0℃ or 32℉).

For the low-level warm air below freezing point, in order to melt the snow falling from the high clouds into rain, the air layer depth of warm air will change between 230m and 460m, which is caused by the vertical temperature gradient between a large number of snowflakes and the melting layer atmosphere. When the thickness of the melting layer atmosphere enters this range, rainwater and partially melted snow will naturally mix.