The coldest air of the season is poised to plunge into the Northeast this coming Valentine's Day weekend. This Arctic blast will not only flirt with some daily records, but will also bring subzero cold to parts of the Midwest and reinforce the cold in the Southeast.
In addition to the bitterly cold temperatures, wind chills are expected to plummet into the 20s and 30s below zero from parts of the Midwest into the Northeast. This has prompted the National Weather Service to issue wind chill watches for a large portion of the Northeast, where "life-threatening" cold conditions will be possible.
Wednesday night into Thursday morning wind chills dropped into the 30s below zero in northern Minnesota, including at the Falls International Airport. The coldest low temperature recorded on Thursday morning in the contiguous U.S. was 35 degrees below zero at Cotton, Minnesota.
Let's first break out the timeline of shivering details, then explain why it won't last long.
See photos of this year's winter season:
Snow, winter weather 2015-2016 season across the U.S.
Valentine's Day weekend arctic outbreak to bring coldest air of the season to Northeast, subzero cold to Midwest
LUBBOCK, TEXAS - DECEMBER 27: A highway worker tries to shield himself while walking to his truck on December 27, 2015 in Lubbock, Texas. Coming on the heels of several strong tornadoes, some northern parts of Texas are experiencing blizzard conditions with wind gusts up to 50 mph and as much as 13 inches of snow forecast. (Photo by John Weast/Getty Images)
NEDERLAND, CO - DECEMBER 15: Steve Hauser plows snow in the Caribou Shopping Center in Nederland, Colorado on December 15, 2015. Snow is expected to continue throughout the day. (Photo by Helen H. Richardson/The Denver Post via Getty Images)
NEDERLAND, CO - DECEMBER 15: A yellow lab waits patiently in his owner's snowy old truck along East 1st Street in Nederland, Colorado on December 15, 2015. Snow is expected to continue throughout the day. The dog looked warm and didn't wait long in the car as his owner returned shortly after an errand in the town. (Photo by Helen H. Richardson/The Denver Post via Getty Images)
DENVER, CO - DEC. 15: Anna Renton, 7, right, relaxes while neighbor Graham Langner, 7, has a snow fight with his nanny, Ashely Kish.The Denver metro area received more snow than expected overnight, closing schools across the city with some areas measuring a foot of snow by the early morning. (Photo by Kathryn Scott Osler/The Denver Post via Getty Images)
LAKEWOOD, CO - DECEMBER 15: Crut Liles clears snow from his walkways outside his home in Lakewood, December, 15, 2015. Many schools in the area are closed due to the snow storm. (Photo by RJ Sangosti/The Denver Post via Getty Images)
DENVER, CO - DEC. 15: A CDOT crew runs their plow truck southbound on Colorado Blvd. near E. 13th Ave. in Denver. The Denver metro area received more snow than expected overnight, closing schools across the city with some areas measuring a foot of snow by the early morning. (Photo by Kathryn Scott Osler/The Denver Post via Getty Images)
Al Frelk walks his dog, Shiba, 10, in Lords Park in Elgin, Ill., on Saturday, Nov. 21, 2015. Asked about the snow, Frelk said, 'It's beautiful, but can be tough to drive in. Though Shiba has been waiting 9 months for this.' The first winter storm of the season dropped more than 10 inches of snow at numerous Chicagoland locations. (Stacey Wescott/Chicago Tribune/TNS via Getty Images)
DENVER, CO - NOVEMBER 17: Snow hit the Denver metro area having an impact on air travel at Denver International Airport. They were clearing out from the snow on Tuesday, November 17, 2015. Raul Hernandez shovels snow in the economy lot. Hernandez and his crew had worked all night to clear snow. (Photo by Cyrus McCrimmon/The Denver Post via Getty Images)
LAKEWOOD, CO - NOVEMBER 11: Brandon Nelli, a student at Colorado Christian University in Lakewood, shovels snow during a Veteran's Day snow storm the moved into the area overnight, November, 11, 2015. Lakewood got almost 3 inches in some areas form the storm. (Photo by RJ Sangosti/The Denver Post via Getty Images)
DENVER, CO - NOVEMBER 11: A blanket of white snow covers Fort Logan National Cemetery during a Veteran's Day snow storm the moved into the area overnight, November, 11, 2015. (Photo by RJ Sangosti/The Denver Post via Getty Images)
MONUMENT, CO. - November 17: Bob Swift clearing his driveway of a deep drift of snow in Monument, CO. November 17, 2015 Monument, CO (Photo By Joe Amon/The Denver Post via Getty Images)
An above-average amount of snow covers a small cabin near where the first snow survey of winter conducted by the California Department of Water Resources in Phillips, California December 30, 2015. REUTERS/Fred Greaves
Cameron Shonnard backflips a jump at Squaw Valley in Olympic Valley, California, December 5, 2015. An El Nino is forecasted for California, and regular precipitation has been welcomed after years of drought. REUTERS/Max Whittaker TPX IMAGES OF THE DAY
Fresh snow clings to trees near Big Bend, California, December 4, 2015. An El Nino is forecasted for California, and regular precipitation has been welcomed after years of drought. Picture taken December 4. REUTERS/Max Whittaker
The U.S. Capitol dome can be seen behind piles of snow removed from parking areas and walkways around the Capitol grounds in Washington January 26, 2016. The snowbound Washington area was resuming partial business on Tuesday as trains and buses restarted near-normal service, while federal offices remained closed following a massive blizzard that hammered the U.S. East Coast. REUTERS/Jonathan Ernst TPX IMAGES OF THE DAY
Floodwaters cover Green Avenue after a winter storm in Manasquan, New Jersey, January 24, 2016. A morning high tide surge of 2 feet followed snowfall of about 2 feet in the first major storm of the season. REUTERS/Dominick Reuter
A couple poses for a photo on a snow pile during a snow storm in Times Square in the Manhattan borough of New York, January 23, 2016. REUTERS/Carlo Allegri TPX IMAGES OF THE DAY
WASHINGTON, DISTRICT OF COLUMBIA, UNITED STATES - 2016/02/15: Snow is once again falling across Washington, D.C on Monday, 15 February 2016. The bitter cold was replaced by snow, sleet and rain Monday in the mid-Atlantic states and the South, but many residents were able to hunker down at home with federal offices and many businesses closed for Washington's Birthday. (Photo by Probal Rashid/LightRocket via Getty Images)
A barn painted with the U.S. flag is seen in the snow covered field in Kanawha, Iowa, United States, January 16, 2016. Iowa will be the first state to hold its primary, with both Democratic and Republican events being held February 1, 2016. Picture taken January 16, 2016. REUTERS/Jim Young
Police officers gather outside the Montgomery County Courthouse, where actor and comedian Bill Cosby will arrive for a preliminary hearing on sexual assault charges, in Norristown, Pennsylvania February 2, 2016. Cosby has been charged with the 2004 sexual assault of Andrea Constand, a former women's basketball team manager at Temple University in Philadelphia, Cosby's alma mater. REUTERS/Mark Makela REUTERS/Mark Makela
Discover More Like This
BACK TO SLIDE
Friday: This potent cold will overspread the Midwest Friday, where highs will struggle to get much above zero in the typically coldest spots of eastern North Dakota, northern Minnesota, northern Wisconsin and the U.P. of Michigan.
Saturday morning: Subzero lows are expected as far south as parts of the southern and eastern Great Lakes, as well as parts of the Corn Belt. Lows in the teens and 20s below zero can be expected in the Upper Mississippi Valley. Wind chills in the Great Lakes and Ohio Valley will be well below zero.
Saturday: The cold blast arrives in the Northeast, mid-Atlantic states and surges into the Southeast. Highs will hold in the teens and 20s in the Boston-Washington corridor, with single digits and teens the most the thermometer can muster in the interior Northeast, Great Lakes, Ohio Valley and Upper Midwest. Some parts of Upstate New York may even struggle to rise above zero. Some daily record cold highs may be set in the Great Lakes and Appalachians.
Sunday morning: Subzero lows are possible in southern New England and the suburbs of New York City and Philadelphia. Wind chills will be even more brutal with wind chills expected to be in the 20s below zero in New England with 30s below zero in portions of the interior Northeast. Farther south, lows in the single digits and teens will drive into the Piedmont of the Carolinas. Thirties and 40s will plunge into parts of north and central Florida. The Upper Midwest won't be quite as cold, but should still have some subzero lows, in spots.
Record Lows Sunday: A few daily record lows are possible Sunday morning, but widespread record lows aren't expected. A few cities that may see records tied or set include Boston (-3 degrees); Worcester (-11 degrees); Providence (-7 degrees); Hartford (-9 degrees); Albany (-10 degrees); New York (2 degrees); Philadelphia (2 degrees).
Sunday: In the Northeast and Midwest, teens and 20s will be the rule for most on Valentine's Day. The Carolinas and Tennessee Valley will hold in the 30s and 40s. Some record cold daily high temperatures are possible in the Northeast, Ohio Valley and Appalachians.
Several cities in the Northeast could see their coldest temperatures of the season so far this weekend.
Boston's Logan Airport hasn't dipped below 0 degrees yet this winter, but could do so Sunday morning. Incidentally, subzero cold is quite rare in the city of Boston. They've only had nine subzero lows so far this century, three of which occurred last winter.
Pittsburgh could also slide below zero Sunday morning, something that happened nine times last winter, but happens, on average, only twice each year.
Why This Won't Last Long
Now for the good news, if you're already starting to get a little winter fatigue. The bitterly cold air will be very short-lived. Temperatures will already begin to warm up a bit starting Monday.
Above: Forecast surface temperature anomalies (above and below average) from the Monday evening mean of the ECMWF ensemble forecast. Note how the coldest anomalies (pink, purple, blue contours) largely disappear by next Tuesday at the end of the loop.
The reason for this is another pattern shift next week.
Essentially, the large northward bulge of the jet stream bringing record warmth to the West, including California and the Desert Southwest, will break down. Weather geeks refer to this as a switch from a positive Pacific-North American oscillation to a negative one.
The corresponding southward plunge of the jet exporting cold air out of Canada into the Midwest and East will then also flatten out next week.
Again, weather geeks would say the Arctic oscillation will switch from negative to positive, meaning the winds around the North Pole will be stronger, keeping the coldest Arctic air bottled up instead of plunging south.
So, expect a February thaw after this weekend's shivering in parts of the Midwest and East by the latter half of next week.