Major Lake-Effect Snow Event Follows Midwest Blizzard

By Alex Sosnowski, Expert Senior Meteorologist

December 18,2012; 7:55PM,EST

On the tail end of a Midwest blizzard, the most substantial lake-effect snow event of the season so far will take place Thursday into the weekend before Christmas.
While the air behind the storm is not severely cold, it will be cold enough to get the Great Lakes snow machine running.
While the intensity of the snow will vary from location to location, and by the minute in some cases where bands of snow persist, up to a couple of feet of snow will be possible downwind of the lakes.

RELATED: Blizzard Aims from Omaha to Green Bay, Marquette

Strong winds during and following the flurries, squalls and bands of lake-effect snow will make for whiteout conditions and extensive blowing and drifting of fallen snow.
During the first part of the lake-effect event, the worst conditions are expected along the eastern shore of Lake Michigan and part of the southern shore of Lake Superior. In some areas along the eastern shore of Lake Michigan, peak gusts can reach near hurricane force with frequent gusts between 50 and 70 mph. Waves on the southeastern end of Lake Michigan can reach between 20 and 25 feet with significant overwash likely. People will not want to venture along the immediate lakeshore for safety reasons.

The temperature will drop just enough, fast enough for roads to become icy rapidly as the squalls move in especially from the southern end of Lake Michigan to parts of Ohio.
Cold air, winds and waves will build eastward over the lakes Friday and Saturday as the lake-effect machine is turned on over lakes Huron, Erie and Ontario.

Snow removal crews will be busy over a large part of the Upper Midwest during the late-week storm and in localized areas of the eastern Great Lakes this weekend. (Photos.com image)

I-90 which parallels the southern shorelines of many of the lakes, including those in Indiana, Ohio and New York, could be significantly impacted by the bands of heavy snow, high winds and poor visibility as the cold air advances eastward into the weekend. Travel along I-196 and the northern part of I-75 in Michigan can be especially nasty.
The worst of the lake-effect snow will ease over the western Great Lakes this weekend but will kick into high gear over the eastern Great Lakes.
Other major highways likely to be severely impacted by lake-effect snow and wind include I-79 in northwestern Pennsylvania and I-81 between Syracuse and Watertown, N.Y., Friday night into Sunday.
Locally heavy snowfall is possible this weekend over the northwest-facing slopes of the West Virginia and western Maryland mountains, as well as the Laurel Highlands and Allegheny Plateau in Pennsylvania.
We will have more information on AccuWeather.com as the storm unfolds later this week.