Yellowstone National Park, Wyoming

Regional Weather Alerts


     

Alert: Red Flag Warning
Area(s): Custer County; Sioux Ranger District Custer National Forest
Effective: 2026-08-06 @ 1:50 am -> 2026-08-06 @ 9:00 pm
Onset: 2026-08-06 @ 12:00 pm -> 2026-08-06 @ 9:00 pm
Severity: Severe
Certainty: Likely
Urgency: Expected
Issued By: NWS Billings MT on 2026-08-06 @ 1:50 am
Headline: Red Flag Warning issued August 6 at 12:50AM MDT until August 6 at 8:00PM MDT by NWS Billings MT
Description: * IMPACTS: Low humidities, hot temperatures, gusty winds, and a
wind shift with a cold front will create erratic fire behavior.


* AFFECTED AREA:
In Southeast MT Fire Zone...132.
In Southeast MT and Northwest SD Fire Zone...133.

* COUNTIES AFFECTED:
In Northwest SD...Harding.
In Southeast MT...Carter...Custer...Fallon.

* COLD FRONT: A cold front will move through Thursday afternoon
and evening shifting winds out of the northwest and increasing
wind speeds.

* WIND: West 10 to 20 mph with gusts up to 30 mph.

* HUMIDITY: As low as 10 percent.

* TEMPERATURES: Up to 95 degrees.

Alert: Red Flag Warning
Area(s): Dawson/McCone/Prairie/Richland/Wibaux Counties; The Lower Missouri River Breaks including the Charles M Russell National Wildlife Refuge; Southern Petroleum and Southern Garfield Counties
Effective: 2026-08-05 @ 5:17 pm -> 2026-08-06 @ 8:00 pm
Onset: 2026-08-06 @ 12:00 pm -> 2026-08-06 @ 8:00 pm
Severity: Severe
Certainty: Likely
Urgency: Expected
Issued By: NWS Glasgow MT on 2026-08-05 @ 5:17 pm
Headline: Red Flag Warning issued August 5 at 4:17PM MDT until August 6 at 7:00PM MDT by NWS Glasgow MT
Description: * WIND...Northwest at 15 to 25 mph with gusts to 35 mph.

* HUMIDITY...As low as 12 percent.

* THUNDERSTORMS...None

* IMPACTS...Any fires that develop will likely spread rapidly.
Outdoor burning is not recommended.

Alert: Lake Wind Advisory
Area(s): Central and Southeast Phillips; Central and Southern Valley; Petroleum; Garfield; McCone
Effective: 2026-08-05 @ 11:29 am -> 2026-08-06 @ 5:15 am
Onset: 2026-08-06 @ 10:00 am -> 2026-08-06 @ 8:00 pm
Severity: Moderate
Certainty: Likely
Urgency: Expected
Issued By: NWS Glasgow MT on 2026-08-05 @ 11:29 am
Headline: Lake Wind Advisory issued August 5 at 10:29AM MDT until August 6 at 7:00PM MDT by NWS Glasgow MT
Description: * WHAT...Northwest winds 15 to 25 mph with gusts up to 35 mph.

* WHERE...Fort Peck Lake.

* WHEN...From 9 AM to 7 PM MDT Thursday.

* IMPACTS...Strong winds and rough waves on area lakes will create
hazardous conditions for small craft.

* ADDITIONAL DETAILS...Waves up to 4 feet are expected.