A deep trough again progressed through the Rockies and evolved to a compact closed mid-level circulation drifting across eastern Nebraska and Iowa on April 18. Weak instability resulted in some isolated thunder near the Iowa border.
Every event with a place to put it; 5 filed by county or forecast zone are drawn at its center, in a lighter ring. Tap one for its entry below.
Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.
The episode as NWS FSD wrote it up.
A deep trough again progressed through the Rockies and evolved to a compact closed mid-level circulation drifting across eastern Nebraska and Iowa on April 18. Weak instability resulted in some isolated thunder near the Iowa border. Snow increased rapidly during the pre-dawn hours, but also dissipated quickly in the late afternoon and evening, leaving behind between 2 and 6 inches snowfall across areas of southwest Minnesota.
The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS Sioux Falls, SD wrote its last area forecast discussion before the first event at Apr 18, 3:26 AM CST, 4 minutes earlier.
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</html>The national radar mosaic for the moment the first event began.
5 winter weather. Local standard time, as filed.
Snow developed rapidly in the early morning hours after 0400CST, with visibility of one mile or less at times from 0630-1300CST.
Snow developed rapidly in the early morning hours after 0500CST, with visibility of a half mile or less at times from 0630-1400CST. Snowfall totaled 4.2 inches at Worthington.
Snow developed rapidly in the early morning hours after 0500CST, with visibility a mile or less at times from 0555-1415CST. Snowfall totaled 5.6 inches 2 miles northeast of Lakefield.
Snow developed rapidly in the early morning hours after 0600CST. Snowfall totaled 1.5 inches at Lake Wilson.
Snow developed rapidly in the early morning hours after 0600CST, with visibility a mile or less at times from 0635-1355CST. Snowfall totaled 3.5 inches at Windom.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Minnesota in 2018Every state in 2018This day in weather historyWarnings in Minnesota, April 2018
NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-10-01. Each event’s entry at NCEI: 754326, 754325, 754324, 754322, 754323.