A historic late-season, multi-day winter storm developed rapidly across the central Plains on Wednesday, April 10. This system spiraled several periods of precipitation through the region. The leading precipitation on April 10 was a mix of rain, freezing rain and sleet from far eastern South Dakota through the Interstate 90 areas of southwest Minnesota and northwest Iowa, changing to snow to the north and west. There were even a few elevated thunderstorms which occurred overnight on April 10-11 and produced some near severe hail, which actually occurred after some initial wintry precipitation. Significant icing was centered around 30 miles either side of the Interstate 90 corridor, with as much as a third to three-quarters inch ice accumulation.
Heavy snowfall developed from the early morning of April 11 and continued into the early morning of April 12 across much of southeast South Dakota into northern portions of southwest Minnesota, which accumulated to 1 to 2 feet during the storm. The most persistent snowfall occurred for areas west to north of Sioux Falls, but even there, a brief period of freezing rain or sleet occurred at some point ahead of the main upper trough passage.
The other aspect of this storm was the intense winds, which gusted at the peak from 40 to 60 mph, producing widespread blizzard conditions across southeast South Dakota and southwest Minnesota. Considerable power outages occurred as transmission lines succumbed to the ice accumulation and wind. At the peak, electric companies and cooperatives estimated as many as 25,000 customers were without power. Many areas were without power for a day or two due to the intensity of the storm.
In fact, the strong winds lofted dust from the Texas/Oklahoma panhandles which caused some of the snowfall toward the latter portions of the event to fall with a brownish color. Ironically, the blizzard postponed the statewide tornado warning drill which was a part of Minnesota Severe Weather Awareness Week.