Thunderstorm Wind in Morton County, North Dakota

Public submitted photos of tree damage across the city of Glen Ullin.

An upper level low and surface cold front combined with a very unstable airmass resulted in severe thunderstorms across western and central North Dakota. Supercell thunderstorms initially produced very large hail before transitioning to a linear storm mode, which led to widespread significant thunderstorm wind gusts. The largest reported hail was 3 inches in diameter, occurring southwest of Medora in Billings County. Measured wind gusts of 60 to 80 mph were common as storms moved across western and central North Dakota. The area with the most significant wind damage occurred across Stark, Morton, Mercer, and McLean Counties. In a swath from Dickinson, to Hebron, to Beulah, to Douglas Bay, to west of Garrison, damage from thunderstorm wind gusts led to winds estimated from 80 to 100 mph. The strongest measured wind gust came from a personal weather station just east of Beulah that reported a gust of 103 mph. Damage included campers turned over, large trees downed, roof damage, power outages, garages destroyed, vehicle damage, siding damage, and dented grain bins.