Slush

Slush, also called slush ice, is a slurry mixture of small ice crystals (e.g., snow) and liquid water. In the natural environment, slush forms when ice or snow melts. This often mixes with dirt and other materials, resulting in a gray or muddy brown color. Often, solid ice or snow will block the drainage of fluid water from slushy areas, so slush often goes through multiple freeze/thaw cycles before completely disappearing. In areas where road salt is used to clear roadways, slush forms at lower temperatures than it would ordinarily, and only in salted areas; this can produce a number of different consistencies over the same geographical area.

Slushfall or slushing is the action of a wet snow falling from the sky.

Slush can be a problem on an aircraft runway since the effect of excess slush acting on the aircraft's wheels can have a resisting effect during take off, which can cause an accident such as the Munich air disaster. Slush on roads can also increase the braking distances for cars and trucks, increasing the possibility of rear end crashes and other accidents.

Slush refreezing in overnight frost can turn to dangerous slippery ice underfoot.

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Wikipedia