Widespread Arctic Blast Sliding South and East

January 9,2016
January's reputation for frigid temperatures will be on full display by this weekend in the nation's midsection as a widespread blast of arctic air begins to take hold of the region. The air mass responsible for the incoming plunging temperatures originated from above the Arctic Circle near the North Pole, as the animation below illustrates.

This animation shows the arctic air (purple shadings) moving from near the North Pole late Monday, Jan. 4 south through Canada and into the Lower 48 by Sunday, Jan. 10.

Areas from the western and northern Great Lakes into the Upper Midwest, northern and central Plains and northern Rockies are likely to see subzero lows (and, perhaps, highs in a few spots) while wind chills may dip as low as 30 degrees below zero.
This weekend's plunge will usher in a pattern change featuring colder-than-average temperatures not just over the Midwest and West, but also into the South and, eventually, the East in the week ahead.
Prior to the arrival of this surge of cold air, above-average temperatures will take hold of many states from the Mississippi River Valley to the East Coast this weekend. This will bring milder conditions to the Northeast, where many cities saw their coldest morning so far this season Tuesday. A few record highs are even possible on Sunday including (current record is in parentheses):

• Philadelphia (63 degrees set in 1950)
• New York City (60 degrees set in 1876)
• Hartford, Connecticut (52 degrees set in 1972)
• Albany, New York (53 degrees set in 1939)

(MORE: Record December Warmth)
A big change is in store for the region as the work week starts. High temperatures will drop more than 20 degrees from Sunday to Monday for much of the Northeast.
Below we have a look at the forecast for the chilly temperatures set to arrive this weekend, followed by a recap of the early week chill in the East.

Widespread Arctic Invasion Continues

Bitterly cold air pushed south across parts of Canada to wrap up the week. That cold air mass is now oozing south into parts of the Lower 48 as a large southward dip in the jet stream develops in the central states.
(MORE: January-March Temperature Outlook)

Where's the Cold Air Now?

As is typical with invasions of arctic air in winter, the air mass will be accompanied by a strong area of surface high pressure plunging south to the east of the Rockies. The pressure gradient between the high and lower pressure in the East will contribute to gusty winds, resulting in low wind chill values as well.
On Saturday, high temperatures only reached the single digits across much of the northern Plains and Upper Midwest. Over parts of eastern North Dakota and northern Minnesota, temperatures stayed below zero the entire day.
Here's a general timing of when the cold air will arrive by day:

• Sunday: Highs 10 to 20 degrees below average will grip the Mississippi Valley, western Great Lakes, and parts of the Deep South.
• Monday: Below average temperatures continue throughout much of the Midwest and South as colder temperatures finally arrive in most of the East Coast.
• Tuesday: Highs 10 to 20 degrees below average from the northern Plains into the Upper Midwest. Near or slightly below average from the Great Lakes to the Northeast.

The map below shows the forecast high temperatures Sunday through Tuesday, when this wave of arctic air will spread southward through the Midwest and Plains.

Forecast Highs Sunday-Tuesday

Many locations will see the lowest temperatures of the season so far. The coldest high temperature International Falls, Minnesota had seen this season was 10 degrees, and the coldest low was 7 degrees below zero. Temperatures fell steadily through much of Saturday, reaching the teens below zero by Saturday night. They may not rise above zero again until at least early next week.
For cities in the Upper Midwest and northern Plains, including Minneapolis and Fargo, North Dakota, highs will struggle to rise out of the single digits. Parts of the Great Lakes and central Plains, including Chicago and Omaha, Nebraska, may only see highs rise into the teens or low 20s.
(FORECAST: Bismarck, North Dakota | Chicago | Minneapolis)
As for low temperatures, single digits and teens below zero are likely in the northern Plains and Upper Midwest. The coldest locations will dip into the 20s below zero. Lows in the single digits above zero are expected from the central Plains to the southern Great Lakes.

Forecast Morning Low Temperatures

Temperatures will feel even colder when factoring in the winds. The "feels like" temperature, or wind chill, will drop into the 20s or even 30s below zero by Sunday across the Dakotas and Upper Midwest.
NOAA's National Weather Service has issued wind chill advisories for several states, including parts of the Dakotas, eastern Nebraska, Minnesota, Wisconsin, Iowa and as far south as northern Missouri.

Forecast Wind Chills

Interestingly enough, despite these cold temperatures, few, if any daily cold records might be set, as we're near the coldest time of the year, climatologically speaking.
For example, daily record lows in Fargo, North Dakota, this time of year are in the 30s or 40s below zero. In Chicago, those daily records are primarily in the teens or 20s below zero.

Early Week Cold Recap (January 4-5)

On Tuesday, temperatures ranged from to 10 to 15 degrees or more below average from Georgia to portions of New York and New England. While not record breaking, for locations like Atlanta, Georgia and Richmond, Virginia, it was the coldest day since Feb. 24-25, 2015. At New York City, Philadelphia and Washington D.C., it was the coldest day since March 6, 2015.
Temperatures plunged as low as 27 degrees below zero Tuesday morning in Clayton Lake, Maine, and 22 degrees below zero at Saranac Lake in the Adirondacks of upstate New York. Subzero lows were also noted across much of New Hampshire and Vermont as well as the Catskills of New York and the nearby Poconos in northeast Pennsylvania. Several locations in southwestern New York and northwestern Pennsylvania also fell below zero.

Observed low temperatures at selected locations in the Northeast on Tuesday, Jan. 5, 2016. For both New York City and Boston, the readings were the lowest since Feb. 24, 2015, when New York hit 4 degrees and Boston bottomed out at 2.

Boston dipped into the single digits and wind chills as low as zero extended as far south as Washington, D.C., Tuesday morning.
Despite that, there were no reports of record lows at any of the major long-term weather observation sites in the Northeast Tuesday.