Another Large Winter Storm, December 26-27, 2021

radar
Radar loop from Duluth, spanning late evening of Sunday December 26 into the afternoon of Monday December 27, 2021.
Source: College of DuPage

Another heavy snow-producer blasted central and northern Minnesota, making it the third time this December that some part of Minnesota received over a foot of snow.

A band of wind-driven snows lifted north and northeastward across Minnesota on the evening of Sunday December 26th, with the snow intensifying and expanding over the northern half of the state. The snow became especially heavy late in the evening near Brainerd, where a spotter had reported 3.5 inches accumulating in one hour. Multiple waves of heavy snow then paraded over the Brainerd Lakes, Grand Rapids, Duluth, and the north shore of Lake Superior, eventually winding down during the afternoon of Monday December 27th.

Another area of heavy snow with strong winds moved across the counties near the border with North Dakota. Blizzard conditions were reported in many of these areas. In the Twin Cities area, the snow only lasted a few hours, but was topped by a glaze of light freezing rain. Icy conditions were common in southern Minnesota, especially south of the Twin Cities.

The total snowfall increased from south to north across the state, reaching maximum values near Brainerd and Hinckley, and also in the higher terrain near Lake Superior. A spotter near St Mathias reported 18 inches, and observers along Highway 210 from Motley and Pillager, through Baxter and Brainerd, to Riverton and Crosby consistently reported 13 - 16 inches.

Another concentrated area of foot-plus accumulations centered on Pine County, with 12-14 inches reported in and around Hinckley, Pine City, Beroun, and Finlayson.

As is often the case, winds off of Lake Superior produced bands of enhanced snowfall intensity in the higher terrain near the lake, yielding some higher totals in parts of St. Louis, Lake, and Cook counties. Outside of the highest totals, most of the northern half of Minnesota received 5-10 inches of snow from this storm.    

To those who pay close attention to geographical snowfall patterns during winter storms, this one was somewhat unusual--not for the locations affected, but for the placement of heavy snow relative to the center of the low-pressure system. Typically, the counter-clockwise circulation around and into low pressure, dictates that areas along and to the right of its path remain on the "warm side" of the system, where precipitation is often in the form of rain. We tend to see the heaviest snow and highest accumulations 100 to 200 miles to the left of the path of a low-pressure system, where the streams of moisture and cold air intersect. In this case, however, the warm side of the storm still had deep enough cold air for snow, and the ingredients for heavy snow were optimized out ahead of and to the right of the storm track. Therefore, those areas received the heaviest snow. The blizzard conditions in northwestern Minnesota were, however, near where one would expect them to be, based on the track of he low pressure.

 

Posted December 27, 2021