Lake-effect snow is a type of snowsquall and is produced in the winter when cold, arctic winds move across the warmer lake water. This picks up energy and moisture, which freezes and is dump on the lee shores.
Higher elevations on the downwind side of this effect can enhance it, created fairly narrow but very intense bands of precipitation. This can drop large amounts of snow in a short period. Areas affected by lake-effect snow are called snowbelts.
It can occur anywhere but is best known in the Great Lake region.
Lake effect rain can also occur if temperatures are not low enough.
Many times lake effect, whether with snow or rain, can also produce thunder and lightning.
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