Flash Flood Watch
Issued by NWS Great Falls, MT

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622
WGUS65 KTFX 181639
FFATFX

URGENT - IMMEDIATE BROADCAST REQUESTED
Flood Watch
National Weather Service Great Falls MT
1039 AM MDT Fri Sep 18 2026

MTZ326-191200-
/O.CAN.KTFX.FF.A.0007.260919T0000Z-260920T0600Z/
/O.NEW.KTFX.FA.A.0008.260919T0000Z-260920T0000Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Gallatin Valley-
Including the cities of Bozeman and Gallatin Gateway
1039 AM MDT Fri Sep 18 2026


The Flash Flood Watch has been changed to a Flood Watch.

&&

...FLOOD WATCH IN EFFECT FROM 6 PM MDT THIS EVENING THROUGH SATURDAY
AFTERNOON...

* WHAT...Flooding caused by excessive rainfall is possible.

* WHERE...The Gallatin Valley in Southwest Montana

* WHEN...From 6 PM MDT this evening through Saturday afternoon.

* IMPACTS...Excessive runoff may result in flooding of low-lying and
  flood-prone locations.

* ADDITIONAL DETAILS...
  - Showers and thunderstorms capable of producing hourly rainfall
    rates up to 0.3 inch, with localized higher amounts, are
    possible.
  - http://www.weather.gov/safety/flood

PRECAUTIONARY/PREPAREDNESS ACTIONS...

You should monitor later forecasts and be alert for possible Flood
Warnings. Those living in areas prone to flooding should be prepared
to take action should flooding develop.

&&

$$

MTZ319-321-323-191200-
/O.NEW.KTFX.FA.A.0008.260919T0000Z-260920T0000Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Helena Valley-Meagher County Valleys-Canyon Ferry Area-
Including the cities of Checkerboard, White Sulphur Springs, Helena,
Townsend, Martinsdale, Toston, Winston, and Ringling
1039 AM MDT Fri Sep 18 2026

...FLOOD WATCH IN EFFECT FROM 6 PM MDT THIS EVENING THROUGH SATURDAY
AFTERNOON...

* WHAT...Flooding caused by excessive rainfall is possible.

* WHERE...The Canyon Ferry Area, Helena Valley, and Meagher County
  Valleys in Central Montana

* WHEN...From 6 PM MDT this evening through Saturday afternoon.

* IMPACTS...Excessive runoff may result in flooding of low-lying and
  flood-prone locations.

* ADDITIONAL DETAILS...
  - Showers and thunderstorms capable of producing hourly rainfall
    rates of between 0.25 inch to 0.5 inch are possible.
  - Some locations impacted include Helena, Townsend, and White
    Sulphur Springs
  - http://www.weather.gov/safety/flood

PRECAUTIONARY/PREPAREDNESS ACTIONS...

You should monitor later forecasts and be alert for possible Flood
Warnings. Those living in areas prone to flooding should be prepared
to take action should flooding develop.

&&

$$

MTZ327-191200-
/O.CON.KTFX.FF.A.0007.260918T2100Z-260920T0000Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Northwest Beaverhead County-
Including the cities of Dewey, Big Hole Pass, Wise River, Chief
Joseph Pass, and Wisdom
1039 AM MDT Fri Sep 18 2026

...FLASH FLOOD WATCH FOR THE SAND CREEK AND BOBCAT LAKES BURN SCARS
REMAINS IN EFFECT FROM 3 PM MDT THIS AFTERNOON THROUGH SATURDAY
AFTERNOON...

* WHAT...Flash flooding and debris flows caused by excessive rainfall
  continue to be possible over the Sand Creek and Bobcat Lakes Burn
  Scars.

* WHERE...A portion of southwest Montana, including the following
  area, Northwest Beaverhead County.

* WHEN...From 3 PM MDT this afternoon through Saturday afternoon.

* IMPACTS...Heavy rainfall over the Sand Creek and Bobcat Lakes Burn
  Scars is expected up to and during the period of the watch.
  Residents near the Sand Creek and Bobcat Lakes Burn Scars 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...
  - Showers and thunderstorms capable of producing locally intense
    rainfall are forecast to develop over the burn scar late this
    afternoon through this evening with additional precipitation
    expected through Saturday, which may lead to flash flooding and
    debris flows.
  - Some locations that may experience flash flooding include...
    Areas near the Sand Creek and Bobcat Lakes Burn Scars, including
    portions of the Pioneer Mountains Scenic Byway.
  - http://www.weather.gov/safety/flood

PRECAUTIONARY/PREPAREDNESS ACTIONS...

You should monitor later forecasts and be prepared to take action
should Flash Flood Warnings be issued.

&&

$$

MTZ317-320-322-191200-
/O.CON.KTFX.FF.A.0007.260919T0000Z-260920T0600Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Little Belt and Highwood Mountains-Big Belt, Bridger and Castle
Mountains-Elkhorn and Boulder Mountains-
Including the cities of Trident, Kings Hill Pass, Battle Ridge Pass,
Elk Park Pass, Neihart, Wickes, Montana City, Clancy, Maudlow,
Corbin, Deep Creek Pass, Homestake Pass, Bozeman Pass, Boulder, and
Monarch
1039 AM MDT Fri Sep 18 2026

...FLASH FLOOD WATCH FOR THE HORSE GULCH AND BURN SCARS OF 2026
REMAINS IN EFFECT FROM 6 PM MDT THIS EVENING THROUGH SATURDAY
EVENING...

* 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...From 6 PM MDT this evening through Saturday 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

PRECAUTIONARY/PREPAREDNESS ACTIONS...

You should monitor later forecasts and be prepared to take action
should Flash Flood Warnings be issued.

&&

$$

Moldan