A powerful late spring storm system swept across the Northern Plains region April 29th into May 1st. Significant amounts of moisture was drawn into the storm from the Gulf of Mexico, leading to heavy amounts of precipitation over west and central North Dakota. Strong cold air advection on the back side of the surface low resulted in a changeover from rain to freezing rain and eventually to heavy wet snow from west to east during this event.
In addition, a tight pressure gradient and strong pressure rises on the back side of the surface low resulted in the development of very strong winds ranging from 40 to 60 mph across much of the region. Some reporting stations observed peak wind gusts in excess of 75 mph.
Parts of western and north central North Dakota were hit the hardest, experiencing a prolonged period of very strong winds, freezing precipitation, and the heaviest snow of up to 14 inches. Impacts here were extreme and devastating, as the ice and heavy wet snow combined with the strong winds to knock down numerous trees and power lines, resulting in the loss of power to thousands, as well as stranding many motorists. Across the southwest and central impacts were less severe, however the widespread blizzard conditions still resulted in numerous road closures and travel advisories. Far south central and eastern North Dakota received very little snowfall but still experienced the high winds.
A preliminary damage assessment by state officials documented an estimated 6.5 million dollars in damages, leading the North Dakota Governor to issue a State Disaster Declaration. Over 1,500 power transmission structures were damaged, and estimated livestock losses were more than 1,000. Also, one direct fatality and one direct injury were attributed to the storm near New England in Hettinger County, where a two-vehicle head on crash occurred due to low visibilities in the blizzard.
See also storm data entries for May 2011.