For cities such as Chicago, Detroit, Philadelphia and New York, this winter is behaving like a houseguest that can’t take a hint that it's time to go.
Even though meteorological winter has officially ended (it runs from December through February), extraordinarily cold temperatures and snowstorms remain the major weather story of the day.
See also: 20 Arctic Photos From the Midst of the Polar Vortex
A renewed surge of frigid Arctic air moved southward from Canada late last week, and now blankets much of the United States. Cold temperature records continue to be set from the Upper Midwest, where several locations have had winters ranking among their top 10 coldest on record, to the Plains and the East. Chicago, for example, had its third-coldest and snowiest winter on record.
The cold front that brought the frigid air south and east was not an ordinary cold front, but rather a sharp boundary between two seasons ushering in a nasty case of weather whiplash to each area it passed through.
In Austin, the temperature on Sunday fell from the springlike lower 70s degrees Fahrenheit at about 9 a.m. to the more wintry 40 degrees Fahrenheit just three hours later.
The same day, temperatures in Billings, Mont., plummeted to -21 degrees Fahrenheit, which broke the all-time record low temperature for the month of March, was -19 degrees, set in 1951.
Also on Sunday, Mason City, Iowa, tied its all-time March record for the coldest daytime high temperature, with a high of just -3 degrees Fahrenheit. This tied a record set in 1948, the National Weather Service said.
On Monday, Green Bay, Wisc., bottomed out at -24 degrees Fahrenheit, which smashed the daily record low there. It was the second-coldest temperature on record for the month of March, and the 9th-coldest temperature recorded in any month at that location. This was also the latest point in the year that Green Bay has ever been that cold.

Temperature departure from average on March 3, 2014, from a computer model. Data is relative to 1979-2000 baseline.
Image: University of Maine
Record lows are anticipated across the Mid-Atlantic and Northeast on Monday night into Tuesday morning, with all-time monthly cold temperature records within reach in Richmond and Philadelphia. A fresh snow cover in those cities will cool the atmosphere further by reflecting the sun's heat back into space. Washington, D.C., where about 6 inches of snow fell on Monday, is likely to be nearly as cold on Tuesday morning as it was in March 1873, when the thermometer plummeted to 4 degrees Fahrenheit.
Put simply, the weather pattern across the U.S. is like a broken record. It continues to feature a broad, deep trough, or dip, in the jet stream across the eastern two-thirds of the country. This pulls more cold air south out of Canada, while at the same time helping to draw milder air into the Western U.S.
In addition, the polar vortex, which is a circulation of air that orbits the Arctic, bottling up extreme cold in that region, has repeatedly wobbled to the south, above southeast Canada, where it has helped inject extra cold air into the air masses crossing the U.S. border with Canada.
There are no signs that the cold weather pattern is going to let up anytime soon, although the extreme cold of this week should ease somewhat. In fact, Tuesday's temperatures along the East Coast will probably be the coldest temperatures the area will see until next winter. The most recent outlook for the next two weeks shows a continued likelihood of below average temperatures from the Rockies eastward through the middle of the month, with above average temperatures and below average precipitation in the West.

Climate outlook for March 11-17, 2014.
Image: NOAA/Climate Prediction Center.
The National Oceanic and Atmospheric Administration will release its official spring climate outlook later this month. It will take recent trends toward an El Nino event, with above average sea surface temperatures appearing in the tropical Pacific Ocean, into account.
The agency’s winter outlook, however, failed to anticipate the extent and intensity of the cold.
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