Yellowstone National Park, Wyoming

Regional Weather Alerts


     

Alert: Flash Flood Watch
Area(s): Red Lodge Foothills; Absaroka/Beartooth Mountains; Northeast Bighorn Mountains
Effective: 2026-05-29 @ 11:15 am -> 2026-05-30 @ 11:15 am
Onset: 2026-05-30 @ 7:00 am -> 2026-05-31 @ 1:00 am
Severity: Severe
Certainty: Possible
Urgency: Future
Issued By: NWS Billings MT on 2026-05-29 @ 11:15 am
Headline: Flash Flood Watch issued May 29 at 10:15AM MDT until May 31 at 12:00AM MDT by NWS Billings MT
Description: * WHAT...Flash flooding and debris flows caused by excessive rainfall
are possible over the Elk, Robertson Draw, and East Side Burn Areas
on Saturday.

* WHERE...Portions of south central Montana, including the following
areas, Absaroka/Beartooth Mountains and Red Lodge Foothills and
north central Wyoming, including the following area, Northeast
Bighorn Mountains.

* WHEN...From Saturday morning through Saturday evening.

* IMPACTS...Periods of heavy rainfall with embedded thunderstorms are
expected over the Elk, Robertson Draw, and East Side Burn Areas
Saturday, possibly beginning early in the morning. Residents near
these burn scars should prepare for potential rapid runoff,
flooding and debris flows. Narrow drainages and low-lying areas are
especially prone to flood. Be sure to stay up to date with
information from local authorities.

* ADDITIONAL DETAILS...
- Periods of heavy rainfall with embedded thunderstorms are
expected across the region. The Elk Burn Area along the eastern
slopes of the Bighorns, and the Robertson Draw and East Side Burn
Areas south of Red Lodge, could experience flash flooding and
debris flows. Stay alert!
- http://www.weather.gov/safety/flood

Alert: Hydrologic Outlook
Area(s): Cascade, MT; Chouteau, MT; Glacier, MT; Hill, MT; Judith Basin, MT; Lewis and Clark, MT; Liberty, MT; Meagher, MT; Pondera, MT; Teton, MT; Toole, MT
Effective: 2026-05-29 @ 5:25 am -> 2026-05-29 @ 7:00 pm
Onset: 2026-05-29 @ 5:25 am
Severity: Unknown
Certainty: Possible
Urgency: Future
Issued By: NWS Great Falls MT on 2026-05-29 @ 5:25 am
Headline: Hydrologic Outlook issued May 29 at 4:25AM MDT by NWS Great Falls MT
Description: ESFTFX

What: Widespread heavy rainfall Saturday into Monday.

Where: Mostly the western portion of North Central MT.

Timing: The heavier rainfall will begin on Saturday and then
diminish on Monday. Rainfall rates of around 0.50 to 0.75 are
possible every 6 hours over a 36 hour period.

Relevant factors: Overall, total precipitation amounts for most
areas will range from 1 to 2 inches. About 10 percent of the area
will receive closer to 3 inches of rainfall.

In terms of flooding, given the recent dry period, most of the area
will be handle the first few inches of rainfall. However, areas that
receive 3 or more inches of rainfall could start to have impacts.

Additionally, there is still a minor snowpack left in the mountains
that could add to runoff concerns as the remaining snow washes out.

Thus some flood statements might be needed later this weekend should
flooding develop over the Plains or along rivers.

Everyone is reminded that should flooding develop, regardless if the
roadway is paved or not, do not drive through any flood waters, as
you do not know if the road has been washed out under the flood
waters.

Please monitor the National Weather Service or the local media this
weekend for further updates on this spring storm.

Alert: Heat Advisory
Area(s): Daniels; Sheridan; Western Roosevelt; Richland; Dawson; Prairie; Wibaux; Northern Phillips; Northern Valley; Eastern Roosevelt
Effective: 2026-05-29 @ 5:02 am -> 2026-05-29 @ 1:15 pm
Onset: 2026-05-29 @ 5:02 am -> 2026-05-29 @ 7:00 pm
Severity: Moderate
Certainty: Likely
Urgency: Expected
Issued By: NWS Glasgow MT on 2026-05-29 @ 5:02 am
Headline: Heat Advisory issued May 29 at 4:02AM MDT until May 29 at 6:00PM MDT by NWS Glasgow MT
Description: * WHAT...Temperatures in the 90s.

* WHERE...Daniels, Dawson, Eastern Roosevelt, Northern Phillips,
Northern Valley, Prairie, Richland, Sheridan, Western Roosevelt,
and Wibaux Counties.

* WHEN...Until 6 PM MDT this evening.

* IMPACTS...Hot temperatures and high humidity may cause heat
illnesses.

Alert: Heat Advisory
Area(s): Central and Southeast Phillips; Central and Southern Valley; Garfield; McCone
Effective: 2026-05-29 @ 5:02 am -> 2026-05-29 @ 1:15 pm
Onset: 2026-05-29 @ 5:02 am -> 2026-05-29 @ 7:00 pm
Severity: Moderate
Certainty: Likely
Urgency: Expected
Issued By: NWS Glasgow MT on 2026-05-29 @ 5:02 am
Headline: Heat Advisory issued May 29 at 4:02AM MDT until May 29 at 6:00PM MDT by NWS Glasgow MT
Description: * WHAT...Temperatures in the mid 90s.

* WHERE...Central and Southeast Phillips, Central and Southern
Valley, Garfield, and McCone Counties.

* WHEN...Until 6 PM MDT this evening.

* IMPACTS...Hot temperatures and high humidity may cause heat
illnesses.

Alert: Hydrologic Outlook
Area(s): Deer Lodge, MT; Flathead, MT; Granite, MT; Lake, MT; Missoula, MT; Powell, MT; Ravalli, MT; Silver Bow, MT
Effective: 2026-05-28 @ 2:51 pm -> 2026-05-29 @ 1:00 pm
Onset: 2026-05-28 @ 2:51 pm
Severity: Unknown
Certainty: Possible
Urgency: Future
Issued By: NWS Missoula MT on 2026-05-28 @ 2:51 pm
Headline: Hydrologic Outlook issued May 28 at 1:51PM MDT by NWS Missoula MT
Description: ESFMSO

What: Widespread Moderate to Heavy Precipitation

Where: Western Montana Counties: Flathead, Lake, Missoula, Powell,
Granite, Ravalli, Deer Lodge, and Silver Bow

Timing: Saturday May 30 through Monday June 1, 2026

Relevant factors:
Total precipitation amounts of 1 to 3 inches with locally
higher amounts possible in higher terrain along the divide.
Ongoing snowmelt and recent precipitation has kept stream and
river levels rising. Anticipate further rises in local
waterways, rockfall and mudslide potential in steep terrain,
as well as possible urban and low-land flooding.

The Clark Fork River near Missoula is currently forecast to reach
near 8 feet by Monday afternoon, June 1.

The Flathead River near Columbia Falls is currently forecast to
reach near 14 feet by Tuesday night, June 2.

Additional information will be provided at or before Noon MDT on May
29th.