Blizzard warnings issued as upper Midwest snowstorm begins to strengthen

By Derek Van Dam and Judson Jones, CNN meteorologists

The first significant winter storm of the season is impacting many across the Dakotas and Minnesota Friday morning. Blizzard conditions are ongoing as winds increase to over 30 to 40 mph across this region, where temperatures have plummeted to below average.

Heavy rain is falling on the warmer side of this storm system and eventually will swing through the Northeast by the early weekend, prompting the Weather Prediction Center (WPC) to issue a marginal risk — level 1 of 4 — for excessive rain Friday.

This strengthening and wide-ranging weather system will move east from Omaha, Nebraska, to New York City. Meanwhile, the West is experiencing an atmospheric river.

Season’s first snowfall to pack a punch

This storm system will usher in enough cold air to create snow and strong winds. This snowstorm is forecast to continue across the upper Midwest Friday.

“Much of the Upper Midwest is under some sort of winter alert as the season’s first significant snowfall is forecast,” CNN meteorologist Dave Hennen says.

Total snow accumulations will range from only 2 to 6 inches. But the winds will gust as high as 60 mph, creating whiteout conditions in portions of the Plains.

A blizzard warning is in place until midday Friday and covers most of northeast South Dakota.

“Travel should be restricted to emergencies only,” says the National Weather Service.

“A large and energetic low pressure system that has brought snow and high winds across the northern Plains and upper Midwest will steadily weaken today as it moves across the Great Lakes and then retreats into Canada tonight.,” the Weather Prediction Center (WPC) says.

You may think it’s too early in the season to talk about snow, but if you’re across the upper Midwest, it’s pretty punctual, if not a few days early. Take, for example, Minneapolis/St. Paul, where the first snowfall of 1 inch or greater occurs around November 16. This Friday, the region could experience “numerous snow showers” that may be “heavy at times,” according to the Twin Cities National Weather Service office.

“Overnight Friday, light snow will move into parts of the Ohio Valley and the Great Lakes, as the snow over the Upper Mississippi Valley tapers off.”

Hennen says another storm this weekend “will drop south out of Canada and will bring a swath of snow to larger Midwest cities like Chicago, Milwaukee, Detroit and Cleveland.”

Heavy rain threat moves Northeast by the weekend

After the storm gives many their first taste of winter across the upper Midwest, it will continue to expand in size and move slowly eastward. The front half of the low pressure will draw precipitation and milder temperatures northward, allowing the threat for locally heavy rain from the Ohio Valley to New England.

“As the system moves eastward, moisture from the Atlantic will stream into parts of the Northeast on Friday. The rain, heavy at times, will move into the Northeast/Mid-Atlantic and the Carolinas,” says the WPC.

This is why they have issued a marginal risk of excessive rainfall over parts of the Northeast on Friday into Saturday morning.

Rainfall totals will range between 1 to 2 inches through the early weekend. Still, localized accumulations could reach 2 to 4 inches across southern New England.
Rainfall will move through the major cities late morning through early afternoon.

Some of this rainfall could fall in only a matter of hours, increasing that risk for flash flooding.

“The associated heavy rain will create localized areas of flash flooding, affecting areas that experience rapid runoff with heavy rain,” the WPC says.

Temperatures behind this storm system will plummet 15 to 25 degrees by the weekend for many East Coast cities, just enough to remind us that winter is right around the corner.

The-CNN-Wire
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