Sioux Falls, SD – Residents in northwest Iowa and along the Missouri River are being urged to prepare for severe thunderstorms expected late Monday afternoon and evening.
According to the National Weather Service (NWS) in Sioux Falls, scattered thunderstorms will begin developing after 5 p.m. Monday, Sept. 22, and may continue through 10 p.m. The system carries the potential for hail up to ping-pong ball size, wind gusts up to 60 mph, and frequent lightning.
The areas at greatest risk include northwest Iowa counties and river-adjacent communities spanning the Iowa-South Dakota border. Sioux City, IA, and nearby towns could see some of the strongest activity.
The Storm Prediction Center (SPC) has placed much of the region under a Level 2 “slight risk,” meaning scattered severe storms are possible. A Level 1 “marginal risk” extends farther into South Dakota, Nebraska, and southern Minnesota.
NWS officials encourage residents with evening plans or outdoor activities to monitor weather updates and be prepared to take shelter quickly if warnings are issued.
“Have multiple ways to receive alerts this evening,” the Sioux Falls NWS office advised in its Monday morning outlook.
Travelers on major routes, including Interstate 29, should also be alert for rapidly changing conditions.
