Question: How does lake effect snow form?

Answer: For the simple answer, lake effect precipitation depends on:

  1. Air temperature- Cold air temperatures over the land
  2. Lake temperatures- The sea surface temperatures are still warm at the surface from the heating during the summer and fall. Water also holds heat better than air.
  3. Wind direction- This is blowing the cold surface air over the lake helping to initiate showers

Lake-effect snow forms when cold air passes over the warmer waters of a lake. Some of the warm water of the lake evaporates into the air and warms the colder air. The warm moist air rises and cools as it moves away from the lake. When the air cools, it releases moisture in a form of precipitation, and if it’s cold enough at the surface and aloft, it will be snow.

A common weather pattern that forms lake effect snow here happens in early winter or in the fall. Since the Great Lakes are still warm and we have cold air with westerly winds it is helping initiate lake effect

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