Severe Flood ● Closed

Flash Flood Watch issued September 19 at 10:06AM MDT until September 20 at 12:00AM MDT by NWS Great Falls MT, United States of America

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

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* WHAT...Flash flooding and debris flows caused by excessive rainfall
are possible over the Horse Gulch area and burn scars from the
summer of 2026.

* WHERE...A portion of central Montana, including the following
areas, Big Belt, Bridger and Castle Mountains, Elkhorn and Boulder
Mountains and Little Belt and Highwood Mountains.

* WHEN...Through this evening.

* IMPACTS...Heavy rainfall over the Horse Gulch area and burn scars
from the summer of 2026 is expected up to and during the period of
the watch. Residents near the Horse Gulch area and burn scars from
the summer of 2026 should prepare for potential debris flow. Be
sure to stay up to date with information from local authorities.
Heavy rainfall could trigger flash flooding of low-lying areas,
urbanized street flooding, and debris flows in and near recent
wildfire burn scars.

* ADDITIONAL DETAILS...
- National Weather Service Meteorologists are forecasting heavy
rainfall over recent burn scars, which may lead to flash flooding
and debris flows.
- Some locations that may experience flash flooding include...
Areas near recent burn scars from the summer 2026 and the Horse
Gulch area.
- http://www.weather.gov/safety/flood

Measurements

Coordinates39.9645, -100.8105
RegionLittle Belt and Highwood Mountains; Big Belt, Bridger and Castle Mountains; Elkhorn and Boulder Mountains
Location Precisioncountry
Issuing AuthorityUnited States of America — us-noaa-nws-en
Cap UrgencyFuture
Cap CertaintyPossible
Cap Expires2026-09-19T18:15:00-06:00

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: WMO WMO WMO WMO

This event as JSON · API and licence

Source updated 30 days ago (Sep 19, 2026 16:08 UTC) · we last heard from WMO Alert Hub (national weather services) 27 seconds ago

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About this location

The agency did not publish coordinates for this warning. The pin is the centre of the country, not the location of the event — read the area name, not the map, for where it applies.

Area as the agency stated it: Little Belt and Highwood Mountains; Big Belt, Bridger and Castle Mountains; Elkhorn and Boulder Mountains

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.