Grand Forks was high 99, low 60. That breaks a high temperature record of 95, set back in 1906. Surprisingly, Grand Forks was 86 degrees on May 11th, 2023 and 85 degrees on May 11th 2024. These are nearly the maximum values since 1907.
Here's some proof that the snow clouds came from the east. The Kewanechee Valley cam is from about 8000ft on Trail Ridge Road, on the west side of the Park.
The snowbanks shown here melted down from about 9 ft high recently
GFS has these dew points, with a very unstable/uncapped atmosphere near Des Moines. This is Monday afternoon/evening. Strong 850mb-500mb winds, low LCL values favorable for tornadoes. Effectively, a dryline will get up into Iowa in the 00z time frame.