Invasions of chilly air from the north become increasingly common during the
second half of September and October. Up north, the air is growing colder by
the day, mainly because all effective sunlight has been lost. Up around the
Arctic Circle, the sun is barely above the horizon this time of year, and
outgoing heat energy greatly exceeds what is being gained.
Friday, expect a touch of autumn across the northern Great Plains and the Prairies of Canada with highs ranging from the 60s in South Dakota to the 40s in Saskatchewan. Chilly air will reach the Midwest and Great Lakes Friday night and Saturday. Some of this cooler weather will be felt across the Northeast Sunday and Monday.
Say, are those snowflakes on the graphic above? Indeed they are! Summer's grip is slipping fast.
Story by AccuWeather.com Senior Meteorologist John Kocet.
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Paul Douglas

Windy With Light Snow Chances Thursday
We'll watch a couple of light snow chances across the state Thursday, along with increasing winds that could cause that snow to blow around. Quieter weather is expected for the weekend, with only a one-day cool down Friday. - D.J. Kayser
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Evening forecast: Low of 27, increasing clouds as a system approaches southern Minnesota
The latest forecast for the Twin Cities and region.
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Afternoon forecast: Warm and sunny, high 40
Our thaw continues with a high of 40 Wednesday. Temperatures will drop somewhat throughout the rest of the week. Keep an eye out for icy cond
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Paul Douglas
Difference Between Weather and Spy Balloons
We may hit 40F today before a Thursday storm brushes us with a slushy coating. 10" may fall on the Wisconsin Dells. I see 30s and a few 40s into mid-February. Check the blog for more details. -Todd Nelson