(Trends Wide) — The first major winter storm of the season is underway for many in the Dakotas and Minnesota. Blizzard conditions are likely as winds will increase to more than 30 to 40 mph in this region, where temperatures will drop below average.
Heavy rains will fall on the warmer side of this storm system and eventually oscillate across the northeast early in the weekend, prompting the Weather Prediction Center (WPC) to issue a marginal hazard – level 1 of 4 – for excessive rain this Friday.
This strong and far-reaching weather system will move east from Omaha, Nebraska, to New York City. Meanwhile, the West is experiencing an atmospheric river.
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The first snowstorm of the season will be very strong
This developing storm system will introduce enough cold air to create snow further north. A snowstorm with significant impacts was forecast in the upper Midwest from Thursday night through Friday.
“Much of the Upper Midwest is under a kind of winter alert as the first significant snowfall of the season is forecast,” says Trends Wide meteorologist Dave Hennen.
The total accumulations of snow will oscillate between 5 and 15 centimeters. But the winds will gust up to 88 kph, creating white storm conditions in some parts of the plains.
Look for strong northwest winds to develop across the area today and continue into Friday. Snowfall is expected tonight into Friday morning, and combined with the wind, will create hazardous travel conditions across parts of the region. #sdwx #mnwx pic.twitter.com/MaHFctCm1O
– NWS Aberdeen (@NWSAberdeen) November 11, 2021
A blizzard warning is in effect through Friday night and covers most of northeastern South Dakota.
“Travel should be limited to emergencies only,” says the National Weather Service. “If you must travel, have a winter survival kit with you. If you get stranded, keep your vehicle.”
“On Thursday, the snow will march south over the North Plains, the Upper Mississippi Valley and parts of the Middle Mississippi Valley by Friday afternoon,” says the Weather Prediction Center (WPC).
You might think it’s too early in the season to talk about snow, but if you’re in the upper Midwest, it’s pretty punctual, if not a few days early. Take, for example, Minneapolis / St. Paul, where the first snowfall of 2.5 centimeters or more occurs around November 16. This Friday, the region could experience “numerous snow showers” that can be “heavy at times,” according to the office of the Twin Cities National Weather Service.
“During Friday night, light snow will move in parts of the Ohio Valley and the Great Lakes as the snow over the Upper Mississippi Valley subsides.”
The threat of heavy rains shifts to the northeast for the weekend
After the storm gives many their first taste of winter across the upper Midwest, it will continue to expand in size and slowly move east. The forward half of the low pressure will draw more precipitation and milder temperatures north, allowing the threat of locally heavy rains from the Ohio Valley to New England.
“As the system moves eastward, moisture from the Atlantic will hit parts of the Northeast on Friday. Rain, heavy at times, will move toward the Northeast / Mid-Atlantic and the Carolinas,” says the WPC.
That is why they have issued a marginal risk of excessive rain in parts of the Northeast from Friday through Saturday morning.
[Friday: Heavy Rain/Gusty Winds] Dry weather with seasonable temperatures continues tonight into Thursday. An approaching cold front will bring a 4 to 6 hour period of heavy rain, gusty winds and perhaps even a few rumbles of thunder during the day Friday. pic.twitter.com/qIxhOFYwmD
– NWS Boston (@NWSBoston) November 11, 2021
Rain totals will range between 25 and 50 millimeters through the beginning of the weekend. However, localized accumulations could reach 50 to 100 millimeters south in New England.
Some of this rainfall could fall within hours, increasing the risk of flash floods.
“The associated heavy rainfall will create localized areas of flash flooding, affecting areas that experience rapid runoff with heavy rain,” says the WPC.
The temperatures behind this storm system will drop between 15 and 25 degrees Fahrenheit by the weekend in many cities on the East Coast, enough to remind us that winter is just around the corner.