There were multiple waves of precipitation that occurred with this major winter storm that lasted for more than two days.
The first wave of precipitation developed during the morning of Wednesday, April 10th where the initial band moved from southern Minnesota, northward into central Minnesota, and west central Wisconsin by the afternoon and evening. This band of precipitation had thunder, sleet and heavy snow that produced several inches of snow across portions of southern and central Minnesota. Most of the heavier precipitation tapered off in the southern quarter of Minnesota, with light snow continuing across central Minnesota, during the afternoon and evening of Thursday, April 11th.
The second wave of precipitation developed in far southern Minnesota after midnight, Thursday morning, April 11th. This band of precipitation had warmer air aloft which led to more sleet, rain, freezing rain, and thunder. This band was similar to the first with the intensity, but had more mixed precipitation.
By the mid morning, the wave of precipitation had moved out of the region, with much warmer air surging northward ahead of a surface low that moved into southwest Minnesota during the afternoon. There were even some severe thunderstorms that developed near Redwood Falls where one inch hail was reported.
In addition to the precipitation Thursday morning, the next weather element developed. This weather element was a significant increase in the wind speeds, with sustained winds of 30 to 40 mph, with gusts of 50 mph or more across a wide areas of central, and southern Minnesota. This created blizzard conditions in portions of southwest, and west central Minnesota. It would have been worse if the precipitation was in the form of all snow, but warmer air aloft led to more sleet and rain, vs snow.
The high winds also created structural damage to power poles and trees. Some freezing rain led to fallen tree limbs and power outages from ice build up. The local emergency manager in Freeborn County had more than 300 downed power poles, which affected 6500 residents. The Waseca County emergency manager also reported numerous power poles blown down across the county. The National Guard was requested for Freeborn and Steele Counties of south central Minnesota due to stranded motorists. The Governor of Minnesota declared a state of emergency due to the widespread power outages, and stranded motorists.
By Thursday afternoon, most of the heavier precipitation and thunderstorms had moved north and east of the area, with mainly light precipitation in the form of drizzle, light snow or sleet in small areas rotating northward as the main storm started to weaken and move overhead. In addition, wind speeds lessened which led to much better visibility in the west. However, the Minnesota Department of Transportation had already closed or not advised travel for a wide area of west central to southwest Minnesota.
The third wave of precipitation was associated with the main upper level system and changed the precipitation over to all snow by early Friday morning, April 12th. By the afternoon, most of the precipitation had ended, but residual light snow or flurries continued as the main system moved off to the east.
Snowfall totals as the storm ended ranged from over 18 inches in portions of west central Minnesota, to 6 to 12 inches across a wide area of central and southern Minnesota. Areas along the Iowa border, which had more sleet and rain, received 1 to locally 4 inches of snow.