Severe Flood ● Closed

Flash Flood Warning issued September 19 at 6:25PM MDT until September 19 at 9:30PM MDT by NWS Riverton WY, United States of America

Icon = what happened · ring colour = how serious: Extreme Severe Moderate Minor

Loading live data… · Marker positions are approximate; severity is labelled in each popup. Sources: USGS, GDACS, NASA EONET, NOAA/NWS, EMSC.

FFWRIW

The National Weather Service in Riverton has issued a

* Flash Flood Warning for...
Southern Fremont County in central Wyoming...

* Until 930 PM MDT.

* At 625 PM MDT, Doppler radar indicated thunderstorms producing
heavy rain across the warned area. Between 2 and 3 inches of rain
have fallen. 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, 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.

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.

Measurements

Coordinates42.8127, -108.5818
RegionFremont, WY
Location Precisionpolygon
Issuing AuthorityUnited States of America — us-noaa-nws-en
Cap UrgencyImmediate
Cap CertaintyLikely
Cap Expires2026-09-19T21:30:00-06:00

Official source

Warnings courtesy of the issuing national meteorological service, via the WMO Alert Hub.

This is an official warning issued by the authority named above. Follow its instructions and those of your local emergency services.

Severity as published by WMO Alert Hub (national weather services).

View original report

Also reported by: NWS NWS NWS

This event as JSON · API and licence

Source updated 29 days ago (Sep 20, 2026 00:26 UTC) · we last heard from WMO Alert Hub (national weather services) 25 seconds ago

On a slow connection? Low-bandwidth version — no map, no scripts, under 14 KB.

Satellite view, before and after

The latest clear Sentinel-2 pass before this event and the earliest one after it.

Before
Sentinel-2 satellite image of the area on 15 Sep 2026, 4 days before this event

15 Sep 2026, 4 days before this event. 20.2% cloud across the tile.

After
Sentinel-2 satellite image of the area on 23 Sep 2026, 4 days after this event

23 Sep 2026, 4 days after this event. 17.6% cloud across the tile.

The white ring marks where the event was reported.

Each image is a preview of a whole Sentinel-2 tile — an area of roughly 110 by 110 km, where one pixel is about 320 metres — not a close-up of the event, which may be a small part of it. "Clear" means under 30% cloud across the entire tile, so the exact place that matters can still be hidden. These are pictures for context, not an assessment of damage.

Contains modified Copernicus Sentinel data 2026, found through the Earth Search catalogue (Element 84) and served from the AWS Open Data Sentinel-2 archive.

Official authorities in United States

If you are there, these are the bodies whose instructions apply. This site is not an emergency service and does not issue warnings.

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What to do

Follow the instructions issued by WMO Alert Hub (national weather services) and your local emergency services. The guidance below is background.

Flood preparation, evacuation decisions, and the dangers of driving or walking through floodwater.

Open Flood Safety Guide →

Earlier flood events in United States

Severe and extreme events of the same kind, before this one. Listed for scale, not because they are connected to it.

Nearby & related events

Disclaimer: figures are automatic feeds from the named agencies and may be revised. Do not use this page for life-safety decisions — follow official local emergency services.