Arctic cold and, in many places, snow and ice is invading the U.S., from northwest to southeast.
The cold has already arrived in the Pacific Northwest, northern Plains and northern Rockies.
In Seattle, highs over the next several days are forecast to be stuck in the 30s.
And some of this cold is penetrating as far south as southern California and Las Vegas, Nev. AccuWeather is cautioning agriculture may be harmed by freezing lows in this region Wednesday and Thursday morning.
Some of the most extreme cold is expected over the next two days in Montana and the Dakotas. Lows Thursday morning are expected to be 30 to 40 degrees (or more in isolated locations) below average.
Great Falls Montana may dip to -15 Wednesday night, and, in Bismarck, North Dakota, highs may not get above zero Thursday. Wind chills could tank as low as -40.
Throughout much of the Dakotas and northern Rockies, winter storm warnings are in effect for 4-8 inches of snow and blowing snow over the next one to two days.
In Colorado, the frigid air is arriving now. This afternoon in Denver, the temperature plunged from the 50s into the 30s in one hour.
The temp in Denver, CO has fallen 19F in the past hour, from 56F to 37F! http://t.co/evDNQiKmLc
— AccuWeather.com (@breakingweather) December 3, 2013
Highs Wednesday and Thursday will hold in the single digits (wind chills below zero), with several inches of snow expected.
The National Weather Service forecast office serving Denver and Boulder says the cold may reach historic levels.
BY VARIOUS MEASURES THIS WILL LIKELY BE THE COLDEST WEEK SINCE DECEMBER 1998…AND THE COLDER RANGE OF SOLUTIONS ARE MORE LIKE DECEMBER 1983. THAT MONTH STAYED COLD AND WOUND UP BEING THE COLDEST DECEMBER ON RECORD…THE SNOW COVER WILL CERTAINLY HELP US GET OFF TO A COMPETITIVE START.
Into the upper Midwest, a combination of bitter cold and snow is also in the pipeline. 6-9 inches of snow are forecast around Minneapolis through Wednesday, with extreme cold to follow Wednesday night and beyond.
Every state thats entirely west of the Miss. River has some form of winter/cold weather advisory (except Kansas, yet) http://t.co/RkLLaR2IBj
— USA TODAY Weather (@usatodayweather) December 3, 2013
Thursday into Friday, the cold extends further south and east – reaching Dallas, St. Louis, Chicago, and Detroit. Amazingly, Dallas is forecast to bask in near 80-degree warmth Wednesday and may be dealing with an ice storm by late Thursday night. As the AccuWeather graphic below shows, a swath of iciness may affect the area from Dallas through Louisville late Thursday and Friday.
The heart of the arctic cold won’t make it to the East Coast during the work week, but enough of it may ooze into the Mid-Atlantic and Northeast by Sunday and Monday for some snow and ice.
The East Coast, including the Southeast, may eventually get a true taste of Arctic air around this time next week.