Iowa, South Dakota Flash Flood Warning | Effective 05/17/2026 01:08

Headline: 
Flash Flood Warning issued May 17 at 3:08AM CDT until May 17 at 5:15AM CDT by NWS Sioux Falls SD
Event: 
Flash Flood Warning
Urgency: 
Immediate
Effective: 
May 17, 2026 - 1:08am
Expires: 
May 17, 2026 - 3:15am
Description: 
At 308 AM CDT, Doppler radar and automated rain gauges indicated thunderstorms produced heavy rain earlier this morning across the warned area. Between 2.5 and 3.5 inches of rain fell with these thunderstorms. Additional rainfall amounts up to 0.5 inches are possible in the warned area overnight. Flash flooding is ongoing or expected to begin shortly. HAZARD...Flash flooding caused by slow moving thunderstorms. SOURCE...Radar and automated gauges. IMPACT...Flash flooding of small creeks and streams, urban areas, highways, streets and underpasses as well as other poor drainage and low-lying areas. Some locations that will experience flash flooding include... Elk Point.
Instruction: 
Turn around, don't drown when encountering flooded roads. Most flood deaths occur in vehicles. Be especially cautious at night when it is harder to recognize the dangers of flooding. Be aware of your surroundings and do not drive on flooded roads.
Area Description: 
Plymouth, IA; Union, SD
Forcast Office: 
NWS Sioux Falls SD
Sender: 
w-nws.webmaster@noaa.gov