Alberta Clipper
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You may not know that its capital is Edmonton. You may not care that it's as big as Texas. But if you live east of the Rockies, you've probably heard the name Alberta on your local weathercast. This Canadian province exports a particular kind of snowstorm to the U.S. It's called an Alberta Clipper, and it brings to the Great Lakes much of their annual snowfall. Hi, I'm Dave Thurlow for the Mount Washington Observatory and this is The Weather Notebook.

An Alberta Clipper is born on the high plains east of the Canadian Rockies. The average clipper then dives southeast, into the Dakotas and Minnesota, and then arcs eastward across the Great Lakes. On this track, a clipper stays hundreds of miles away from the mild waters of the Atlantic or the Gulf of Mexico. This means your average clipper is moisture-deprived, so it won't drop huge amounts of snow. Instead of two or three feet, it'll leave just a few inches on a narrow track that goes by places like Milwaukee or Detroit.

Once in a while, a clipper moves across the Appalachians and takes on new life as a nor'easter. That happened in grand fashion on February 6, 1978, when a modest clipper turned into the great New England Blizzard of '78.

You'll likely see more clippers than usual during La Nina years, like this one. That's when the jet stream often dives south across the Great Lakes. This year, the Lakes were one of only a few spots in the nation where people actually saw a white Christmas, thanks to the Alberta Clippers.

Today's writer is Bob Henson. Please be sure to visit our website at mountwashington.org. for more information on Alberta Clippers or any kind of snowstorm. Support for The Weather Notebook comes from Subaru and the National Science Foundation.