AccuWeather map, 2/19/21.
SIOUX FALLS, S.D. (KELO.com) — Following the stormiest weather pattern in decades across much of the United States along with the coldest conditions experienced in a generation for most of the South Central region, a major shift in the weather pattern is forecast to begin this weekend — and it could bring relief that could last through the end of February.
A major onslaught of winter storms and brutal Arctic cold has left millions in the middle of the country shivering, including many who have been struggling to stay warm without power in Texas this week. At peak, nearly 4 million people in the Lone Star State were trying to get by without power and heat early this week, and 2.5 million were still without power on Wednesday morning. The extreme cold and other issues related to power outages, such as carbon monoxide poisoning, turned deadly.
AccuWeather meteorologists say the upcoming pattern change will set off not only an upward trend in temperatures but also a thaw and a break from big storms over much of the Central states.
“The atmospheric traffic jam that was contributing to a major buckle in the jet stream will break down in the coming days,” AccuWeather Senior Meteorologist Brett Anderson said. That buckle was the culprit behind the brutal cold that surged all the way southward to the Gulf Coast this week.
“As this [pattern shift] happens, the polar vortex is expected to retreat to northwestern Canada and allow a milder Pacific air to flow across much of the U.S. and southern Canada from this weekend through next week,” Anderson explained.
During next week, temperatures over the Plains are forecast to climb 30 to 50 degrees from their frigid levels experienced during the middle of this week. In some areas, the temperature reversal may approach 60 degrees. The rebound will end up delivering temperatures several degrees above average for the latter part of February.
For example, temperatures dipped to 2 below zero Fahrenheit at Dallas in the depths of the frigid air on Tuesday. The normal high for Feb. 16 is 60 and the normal low is 39, and the mercury had not dropped below zero since Dec. 23, 1989. Temperatures are forecast to creep to 33 degrees on Friday afternoon. That would be the first temperature to reach above freezing since Saturday afternoon, Feb. 13.
For those worn out dealing with the bitterly cold air, frozen pipes and water plant treatment power outages, which led to boil water advisories in some communities, the news of weather to come this weekend may come as even more of a relief. The temperature in Dallas is forecast to climb into the 40s on Saturday to near 50 on Sunday and then the 60s or higher for most days next week.
The temperature turnaround will also be felt farther north across the Plains — all the way to the Dakotas and farther to the northeast, including to the coast of New Jersey, Massachusetts and Maine.
Bone-chilling temperatures have left some areas of the North Central states colder than Siberia and Alaska. Across the northern Plains and Upper Midwest, cities such as International Falls, Minnesota, and Grand Forks, North Dakota, spent more than a week without high temperatures breaking zero degrees. That stretch of subzero cold lasted from Feb. 6 to Feb. 14 in both cities. By Sunday, both of these cities are forecast by AccuWeather to surpass the freezing mark.
In Fargo, North Dakota, where the temperature failed to climb above zero from the evening of Feb. 9 through the early afternoon of Feb. 16, temperatures are projected to reach the 20-degree mark on Saturday and then finally climb above freezing on Sunday. Once this happens, it will be the first above-freezing temperature since Jan. 20. for the northern Plains city.
Elsewhere, places such as Minneapolis have experienced more than 10 straight days with temperatures 20 degrees below average. In fact, the temperature hasn’t cracked the freezing mark since Feb. 4. Highs are finally expected to nudge just above freezing on Sunday.
In the Northeast, the temperature recovery is forecast to be much less dramatic, when compared to the Central states. However, the weather turnabout will still be noticeable. Most of the region can expect a moderating trend of 10-20 degrees from this weekend to next week.
Temperatures are forecast to reach the 40s most days next week in New York City, and highs are projected to be in the 50s in Washington, D.C., and within a few degrees of 40 in Boston. That will bring temperatures to right around normal in New York City, where the normal high is 44 on Feb. 24. Highs could near Boston’s normal of 41 degrees for the same date, and temperatures could even surpass D.C.’s normal high of 49.
If there was not such an extensive swath of snow on the ground, temperatures would rebound at an even faster pace, AccuWeather forecasters explain.
“An extensive snow pack across nation will limit how much warming there is initially, but, compared to what it has been like recently over the Plains and Midwest, the upcoming pattern will be a relief,” Anderson said.
On Tuesday, a new record was set for the highest percentage of the lower 48 states covered with snow. The new record of 73.2% beat the old record of 70.9% set on Jan. 12, 2011. A year ago at this time, snow covered only 35.5% of the contiguous states. Records for snow coverage in the U.S. have been kept since 2004.
However, Anderson added, “Throw in some late-February sunshine, and it should feel a whole lot better, even in the Northeast, where the temperature rebound may be less dramatic since the cold air was less severe to start with.”
This pattern will tend to whisk storms along at a fast pace, which will also prevent the storms from becoming very strong. The quick movement of the storms should also limit the amount of moisture the systems can tap into from the Gulf of Mexico.
Meteorologists would love to say that the worst of the storms and cold are over for this winter across the U.S., and, for the South Central states, that is likely the case. But even though the magnitude of cold may not approach the severity of the middle of February, winter weather won’t be over yet.
One such storm will roll eastward across the North Central and Northeast states from Sunday to Monday with mainly light snow.
“There can be some surges of cold coming down into the Plains and East, but they will tend to be brief during the last part of February to perhaps the first few days of March,” Anderson said.
“There can, and probably will, be waves of Arctic air that can bring periods where temperature departures of 15-25 degrees below average for the date occur, especially in the North Central states,” AccuWeather Lead Long-Range Meteorologist Paul Pastelok said.
And this is the time of year when normal temperatures trend upward. Chicago’s normal high on Feb. 18 is 36, and the normal low is 21. However, during the second week in March, the normal high and low temperatures are 45 and 28 degrees respectively.
During the second week of March, New York City’s normal high climbs to 48 degrees, and the normal low is 34.
Temperature departures of 15-25 degrees below average in March are not a difficult benchmark for Mother Nature to achieve as the air across Canada typically remains very cold despite a general warming trend across the U.S. Brief buckles in the jet stream can easily draw colder air southward.
“At some point in the coming weeks, the polar vortex will return,” Pastelok said, but the next round of cold air will likely take aim at western Canada before sinking southward into the Northwest.
“There can still be below zero Fahrenheit temperatures in March, and this is a possibility this year over the northern parts of the nation, especially from the interior Northwest to the northern Plains, Upper Midwest and northern New England,” Pastelok added.
Even though the pattern is expected to allow more mild-mannered storms over the next week or two, that does not mean that systems will stop dropping snow and ice and causing disruptions to daily activities on occasion. However, there should be more time between storms, and the overall scope of snow and ice should be smaller. Precipitation is not expected to be quite as intense, when compared to recent weeks in February.
There is at least one part of the country that has avoided the big winter storms in recent weeks, and that is the northern Plains.
“Snowfall has been scarce so far in February from parts of eastern Montana to much of the Dakotas and most of Minnesota,” Anderson said.
Fargo typically picks up 7 inches of snow during February but has not even recorded 0.1 of an inch. The weak storms that are expected to sweep across the northern part of the nation during the latter part of February to early March may actually erase some of the precipitation deficit in the region.
March is typically a busy month for storms, including some potent storms, and there is no reason to suggest that the upcoming month will behave like a lamb all the time and everywhere.
“In summary, a break is coming, but winter is not done yet,” Pastelok said.
( AccuWeather senior meteorologist, contributed this report.)
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