While the Great Salt Lake definitely gives the Wasatch Front and Wasatch Mountains lake effect snow, the best, perhaps, lake effect around the world is seen in the populated areas around the Great Lakes.
What is lake effect? Simply put it is precipitation that would not have formed had there been no body of water to travel over. For the Wasatch Front, that body of water is the Great Salt Lake. For the Midwest, those bodies of water are the Great Lakes.
How does it form then? As cold air moves over a warm body of water, water begins to evapotranspire and rise up into the cold air. As this water vapor moves up into the atmosphere, the cold air condenses the water vapor into clouds. These clouds will eventually begin to snow on the downwind shore.
Here’s the tricky part. To forecast lake effect snow, conditions have to be just right. For the Great Salt Lake, there has to be limited steering level directional shear (What?!? That just means winds going up in the atmosphere have to be roughly the same flowing in the same direction) and a temperature difference of at least 16° C between lake and 700 mb (that is about 10,000 ft above sea level).
So, if conditions are setting up just right, how come one area will get dumped on with snow while just a few miles down the street absolutely no snow will fall? Lake effect snow bands are extremely local and can vary in intensity within just a few miles.
In 2001 Buffalo, NY saw 82.3 inches of snow from December 24th to December 28th. Just down the road…only a few inches. Here in Utah, Olympus Cove can get a couple of feet of snow while a few miles west will receive 1 or 2 inches.
What is the snowiest part of the country due to lake effect? That would the upper peninsula of Michigan where snow coming off of Lake Superior dumps 250-300 inches of snow in that area.
The Great Salt Lake gives Salt Lake City about 10% of its annual precipitation and allows for average snowfalls of 500 inches and more in the Wasatch Mountains southeast of the lake.
So what do you need for lake effect snow? A nice cold pocket of air moving over a warm body of water, winds that are flowing through all levels in the atmosphere in roughly the same direction, and a big temperature difference between lake and up in the atmosphere are all requirements.
Neil Opperman
Meteorologist/Weather Producer
