MARSHALL - Another weather record has fallen in Marshall.
Less than a week after hitting a record-setting 63 degrees, temperatures climbed to 57 in Marshall on Tuesday, which broke the record of 54, set in 1990, the National Weather Service in Sioux Falls, S.D., said.
The warm weather is a result of North Atlantic arctic oscillation, which, in effect, has been shielding Minnesota from La Nina effects that would otherwise bring in cold temperatures and plenty of precipitation at this time of year, the NWS said.
Kerry Hankl, a meteorologist with the NWS, said that weather pattern, while not extraordinary, has been extremely persistent this month.
"It's really affecting us by keeping us dry and mild," Hankl said. "We just haven't seen a lot of precipitation because of that and we haven't had a lot of cool air filtering down into the area."
Hankl said the kind of temperatures southwest Minnesota has been experiencing for most of this month can also be attributed to a total absence of snowpack.
The median snow cover at this time of year is between 5 and 10 inches, according to the Minnesota Climatology Office.
"Generally, when you have that snowpack you have a better ability to get that cold, arctic air to settle into an area," she said. "And we're not seeing that anywhere within the region. If you have a good, solid couple of inches of snow on the ground, generally the surface air has a tough time warming up as quickly compared to grassy areas because snow can actually reflect heat. That's when you get those really cold overnight temperatures."
Temperature-wise, things are about to change rather drastically, however, Hankl said. A cold front that was expected to push through the area Tuesday night will keep temperatures in the 30s today. The real cold air - the kind Minnesotans are used to at this time of the year - should creep into the area tonight and stick around through Thursday, as highs will stay in the teens. The low tonight could fall into the single digits.
Hankl said the colder temps could be accompanied by some snow, but it probably won't amount to much because it's a fast-moving system. "A dusting or so," Hankl said. The chances of snow today are 40 percent, the NWS?said. Northwest winds are also expected to kick up to 25-30 mph and that wind will continue to blow throughout the night.
Hankl expects temperatures to rebound back above freezing by this weekend. She said after Thursday, little or no snow is expected for at least the next five days.