An early spring snowstorm will be affect a large portion of the Northern Plains beginning tonight and continuing through Wednesday afternoon. This storm will bring a variety of weather including heavy snow, freezing rain, and widespread blowing snow to much of the Dakotas, Nebraska, and Minnesota.
Precipitation is expected to develop early this evening across south central South Dakota. This precipitation will rapidly spread northeast through the night. With the large difference in temperatures across the region, the impact of this storm will really vary. Total snowfall accumulation and ice accumulation graphics can be found be clicking the link or scrolling to the bottom of this article.
Here is a summary of expected conditions over different portions of the region.
East central and south central South Dakota...including Huron, Mitchell, Brookings, Lake Andes, and Chamberlain:
Precipitation will begin as freezing rain or sleet by late this evening. As colder air continues to move in, the freezing rain will change to sleet and then snow late tonight and Tuesday. By Tuesday afternoon, most of this area is expected to be all snow. The snow is expected to continue into Wednesday morning before gradually coming to an end Wednesday evening. Winds tonight will increase to 20 to 40 mph and remain strong through Tuesday night. Once precipitation changes to snow, widespread blowing snow can be expected with visibilities less than one half mile at times.
Portions of southeast South Dakota and southwest Minnesota...including Sioux Falls, Marshall, Pipestone and Yankton:
Rain will develop this evening. As colder air gradually moves in late tonight, rain, sleet and freezing rain can be expected by dawn on Tuesday. A few locations may see as much as an inch of sleet late tonight and Tuesday morning. Over southwest Minnestoa, freezing rain may persist longer into the morning and a tenth to a quarter inch of ice accumulation is possible before precipitation changes to snow or sleet. Precipitation may diminish in intensity or even stop for a period on Tuesday afternoon before another area of freezing rain or sleet moves in toward sunset on Tuesday. The freezing rain and sleet is expected to change to all snow after midnight Tuesday night with snow continuing into Wednesday night. Winds of 20 to 40 mph are expected to develop tonight and continue through Wednesday. Once precipitation changes to all snow, widespread blowing snow can be expected with visibilities less than one half mile at times.
Portions of far southeast South Dakota, southwest Minnesota, far northeast Nebraska, and northwest Iowa...including Sioux City, Worthington, Spencer, and Storm Lake:
Rain will spread across the area tonight and continue into early Tuesday morning. There may be a brief period of freezing rain late tonight near interstate 90 in Minnesota. Rain may diminish or even end for a period on Tuesday afternoon. More rain is expected to move into the area on Tuesday evening. As colder air moves southeast, rain may change to freezing rain late Tuesday night into Wednesday morning. Freezing rain and sleet will gradually change to snow Wednesday afternoon and Wednesday night. The exact timing of when precipitation changes to freezing rain and snow remains uncertain across this area. It currently appears that less than a tenth of an inch of ice with 1 to 5 inches possible with the greatest accumulations near Interstate 29 and Interstate 90. In additional winds of 20 to 35 mph are expected to Tuesday afternoon and continue through Wednesday. Once precipitation changes to all snow, this will cause blowing snow reducing visibilities to less than a mile at times.
For more information, please see:
Total forecast ice accumulation from tonight through Tuesday night
Total forecast snow accumulation from tonight through Wednesday night