How Lake Effect Snow Develops

Many of us know that lake effect snow develops over the Great Lakes every winter, dumping plenty of snow on Northern Michigan each year.

But have you ever considered how or why this lake effect snow is made?

Lake effect snow generates from cold air traveling over the open waters of the warm, moist Great Lakes. As the warm, moist air rises into the atmosphere, it combines with the cold air. This leads to cloud development and narrow bands of snow.

There are many “ingredients” necessary in determining how much snow will develop, and where it will fall.

First of all, the wind direction is a primary “ingredient.” Depending on the wind direction, this gives forecasters an idea of where the heaviest bands of snow will generate.


For example, our Northwest winds give an indication to our Doppler 9&10 Weather Team that Alger, Antrim, Charlevoix, Chippewa, Crawford, Houghton, Kalkaska, Keweenaw, Luce, Mason, Oceana, Otsego, and Schoolcraft counties will receive the most snow.

On the other hand, Southwest winds lend to Antrim, Benzie, Charlevoix, Chippewa, Emmet, Leelanau, Mackinac and Manistee counties having the most snow dumped on them.


This is all due to what meteorologists call fetch.

Fetch is the distance the wind travels over the open water surface. The longer the fetch, the greater amount of heat and moisture available, which leads to more snowfall.

Another “ingredient” is the temperature of the air versus the water.

A key component or good indicator of lake effect snow is that the temperature of the water is 23 degrees Fahrenheit warmer than the temperature of the air at 5,000 feet up in the atmosphere.

Lastly, the physical geography of the land plays an important role.


More lake effect snow is in the forecast for Wednesday evening through the rest of your work week. Great news for skiers and snowboarders! Stay with the Doppler 9&10 Weather Team for updates. You can always check the latest forecast on our weather page.