Lake effect snow

Lake effect snow, which can be a kind of snowsquall, is produced in the winter when cold, arctic dry winds move across long expanses of warmer lake water, picking up water vapor which freezes and is deposited on the lee shores. This effect is improved when the moving air mass is uplifted by the orographic effect of higher elevations on the downwind shores. This uplifting can produce narrow, but very intense bands of precipitation, which deposit at a rate of many inches of snow each hour and often bringing copious snowfall totals. The areas affected by lake effect snow are called snowbelts. This effect occurs in many locations throughout the world, mostly in the Northern Hemisphere, but is best known in the populated areas of the Great Lakes of North America. The lake effect from the Great Salt Lake in Utah helps to create "The Greatest Snow on Earth". Since the Great Salt Lake never freezes, the lake effect can affect the weather along the Wasatch front year around.

If the air temperature is not low enough to keep the precipitation frozen, it falls as lake effect rain. In order for lake effect rain or snow to form, the moving air must be cooler and also less humid than the surface air. specially, the air temperature should be 15 to 25°C cooler than the water, and the dew point at the altitude where the air pressure is 850 mb should be 13°C lower than the dew point of the air at the surface. Lake effect of very cold air over still warm water in early winter can produce thundersnow, snow showers accompanied by lightning and thunder.