BISMARCK, North Dakota — The latest blast of frigid Arctic air to blanket the Dakotas soon will give way to warmer Pacific air, but it will leave behind a legacy of shattered cold-weather records across the two states.
The North Dakota cities of Grand Forks, Fargo, Jamestown, Minot, Dickinson and Bismarck all experienced record-low maximum temperatures Saturday for the date. Grand Forks also set a record Sunday. National Weather Service reports show that the temperature did not rise above zero in any of those cities, and in Minot and Grand Forks it didn't get any warmer than minus 11 on Saturday.
In South Dakota, Sioux Falls, Rapid City and Aberdeen set similar records over the weekend, according to weather service data. Rapid City — where temperatures never rose higher than 2 above and dropped as low as minus 18 — had record low temperatures and record low maximum temperatures on Saturday and Sunday.
"Basically, it was cold Canadian air rotating on down," Tony Merriman, a weather service meteorologist in Bismarck, said Monday.
It has been one of the coldest winters in recent memory in the region. For the South Dakota cities of Aberdeen, Watertown and Sisseton, the "meteorological winter" — December through February — was one of the top 10 coldest on record, according to the weather service office in Aberdeen. Records for Aberdeen and Watertown date back 121 years. This winter in Pierre and Mobridge was among their top 20 coldest on record. Officials blamed the Alberta clipper systems that swept down from Canada, bringing Arctic air and strong winds.
Fargo — North Dakota's largest city — experienced its 17th coldest winter. At the airport in Grand Forks, North Dakota, it was the third-coldest winter on record. That city had 71 days with the minimum temperature at or below zero degrees, nearly double the norm and third-most on record.
The mid-winter warm-ups that typically intersperse with the cold also were shorter this season, weather service data manager Mark Ewens said.
"The hallmark of this winter is the consistency of the cold," he said.
Temperatures could have been even colder had there been more snow on the ground, since snow cover promotes cooling at night and less warming during the daytime.
"It is a good thing we did not have to find out how cold it may have been," the Aberdeen weather office said in a statement.
Warmer Pacific air will be moving into the region as the Arctic air moves east. Wind chills early Monday in the two states were in the minus teens and 20s, but the forecast called for lows above zero and high temperatures in the teens, 20s and 30s by midweek.
"I wouldn't be surprised if it's not the last time we see these kinds of (cold) temperatures," Merriman said. "But March is a transition month. We should be seeing a lot warmer temperatures by the end of the month."
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