Wyoming Severe Flash Flood Warning | Effective 09/19/2026 18:29

Headline: 
Flash Flood Warning issued September 19 at 7:29PM MDT until September 19 at 9:30PM MDT by NWS Riverton WY
Event: 
Flash Flood Warning
Urgency: 
Immediate
Effective: 
September 19, 2026 - 6:29pm
Expires: 
September 19, 2026 - 8:30pm
Description: 
At 729 PM MDT, Doppler radar indicated thunderstorms producing heavy rain across the warned area. Between 2 and 3 inches of rain have fallen. Additional rainfall amounts of 1 to 2 inches are possible in the warned area. Flash flooding is ongoing or expected to begin shortly. HAZARD...Flash flooding caused by thunderstorms. SOURCE...Radar indicated. IMPACT...Flash flooding of small creeks and streams, highways, streets and underpasses as well as other poor drainage and low-lying areas. Some locations that will experience flash flooding include... Mainly rural areas of Southern Fremont County near Lyons Valley. This includes the following streams and drainages... Little Popo Agie River, Grant Young Ditch, Monument Draw, North Fork Ballenger Draw, Popo Agie River and Government Draw.
Instruction: 
Turn around, don't drown when encountering flooded roads. Most flood deaths occur in vehicles. Be aware of your surroundings and do not drive on flooded roads. Please report observed flooding to local emergency services or law enforcement and request they pass this information to the National Weather Service when you can do so safely.
Area Description: 
Fremont, WY
Forcast Office: 
NWS Riverton WY
Sender: 
w-nws.webmaster@noaa.gov