lake-effect snow

[low_delta]

Lake effect snow is a unique event that occurs on large scale only around the Great Lakes of North America.. While there are some small-scale lake effects around the world, the Great Lakes have a truly unique micro-scale weather phenomenon.

The right combination of geographic factors must be present for lake-effect snowstorms to materialize. A large body of water must be upwind of the area to modify the cold air, and this location must be far enough from the equator so that winter temperatures can be sufficiently cold enough for the precipitation to fall as snow. However, the climate cannot be so cold that the large body of water freezes over completely, or there would be no modifying influence to the cold air.

The body of water must be large enough to warm the air as it travels over the lake, but not large enough to warm it above the freezing point. A large land mass of continental dimensions must lie upwind of the lakes to supply large air masses of cold air.

-John Malan, meteorologist

Comments

[cynnerth.livejournal.com]

That's really interesting! I never knew the explanation for it.

[emschin.livejournal.com]

How interesting. I never quite understood what "lake effect" snow was. Just had a general notion that "it happened" near the lake.
When I see all the things that must be present, I can see how the Great Lakes Region is the only one who has it.

[low-delta.livejournal.com]

I knew how it worked, I just didn't know it was that rare.

And notice that we get it here, but the moisture from the lake only has an effect for a mile or so, unless there's an east wind.

[cynnerth.livejournal.com]

We definitely got lake effect snow sometimes when I lived in western Milwaukee, several miles west the lake. That must have been because of the easterly wind. At the time, I figured it was because Milwaukee was by the lake.