Yellowstone National Park, Wyoming

Regional Weather Alerts


     

Alert: Winter Weather Advisory
Area(s): Pryor/Northern Bighorn Mountains; Northeast Bighorn Mountains
Effective: 2026-05-18 @ 3:06 am -> 2026-05-18 @ 1:00 pm
Onset: 2026-05-18 @ 3:06 am -> 2026-05-18 @ 1:00 pm
Severity: Moderate
Certainty: Likely
Urgency: Expected
Issued By: NWS Billings MT on 2026-05-18 @ 3:06 am
Headline: Winter Weather Advisory issued May 18 at 2:06AM MDT until May 18 at 12:00PM MDT by NWS Billings MT
Description: * WHAT...Snow and blowing snow. Total snow accumulations between 3
and 6 inches, greatest in the Bighorn Mountains. Winds gusting as
high as 45 mph.

* WHERE...In Montana, Pryor/Northern Bighorn Mountains. In Wyoming,
Northeast Bighorn Mountains.

* WHEN...Until noon MDT today.

* IMPACTS...Snow and blowing snow will impact back country recreation
and travel along Highway 14 through the Bighorn Mountains.

Alert: Frost Advisory
Area(s): Kootenai/Cabinet Region
Effective: 2026-05-17 @ 6:01 pm -> 2026-05-18 @ 9:00 am
Onset: 2026-05-18 @ 1:00 am -> 2026-05-18 @ 9:00 am
Severity: Minor
Certainty: Likely
Urgency: Expected
Issued By: NWS Missoula MT on 2026-05-17 @ 6:01 pm
Headline: Frost Advisory issued May 17 at 5:01PM MDT until May 18 at 8:00AM MDT by NWS Missoula MT
Description: * WHAT...Temperatures between 25 and 34 degrees will result in frost
formation.

* WHERE...Kootenai/Cabinet Region.

* WHEN...From midnight tonight to 8 AM MDT Monday.

* IMPACTS...Frost could harm sensitive outdoor vegetation. Sensitive
outdoor plants may be killed if left uncovered.

* ADDITIONAL DETAILS...Temperature ranges include: 31 to 35 degrees
in Eureka, 25 to 28 in Olney, 32 to 36 Libby and Troy areas, 30 to
35 south of Libby to Happys Inn and 26 to 31 Marion and Yaak areas.

Alert: Frost Advisory
Area(s): Lower Clark Fork Region
Effective: 2026-05-17 @ 6:01 pm -> 2026-05-18 @ 9:00 am
Onset: 2026-05-18 @ 1:00 am -> 2026-05-18 @ 9:00 am
Severity: Minor
Certainty: Likely
Urgency: Expected
Issued By: NWS Missoula MT on 2026-05-17 @ 6:01 pm
Headline: Frost Advisory issued May 17 at 5:01PM MDT until May 18 at 8:00AM MDT by NWS Missoula MT
Description: * WHAT...Temperatures between 25 and 34 degrees will result in frost
formation.

* WHERE...Lower Clark Fork Region.

* WHEN...From midnight tonight to 8 AM MDT Monday.

* IMPACTS...Frost could harm sensitive outdoor vegetation. Sensitive
outdoor plants may be killed if left uncovered.

* ADDITIONAL DETAILS...Temperature ranges include:28 to 32 degrees in
Thompson Falls, 30 to 34 degrees in Plains, 33 to 37 degrees in
Noxon, 25 to 28 degrees in Haugan, 29 to 32 degrees in St. Regis,
and 29 to 34 degrees in Alberton.

Alert: Frost Advisory
Area(s): Flathead/Mission Valleys; Missoula/Bitterroot Valleys
Effective: 2026-05-17 @ 6:01 pm -> 2026-05-18 @ 10:00 am
Onset: 2026-05-17 @ 9:00 pm -> 2026-05-18 @ 10:00 am
Severity: Minor
Certainty: Likely
Urgency: Expected
Issued By: NWS Missoula MT on 2026-05-17 @ 6:01 pm
Headline: Frost Advisory issued May 17 at 5:01PM MDT until May 18 at 9:00AM MDT by NWS Missoula MT
Description: * WHAT...Temperatures as low as 28 degrees will result in frost
formation.

* WHERE...Flathead/Mission Valleys and Missoula/Bitterroot Valleys.

* WHEN...From 8 PM this evening to 9 AM MDT Monday.

* IMPACTS...Frost could harm sensitive outdoor vegetation. Sensitive
outdoor plants may be killed if left uncovered.

* ADDITIONAL DETAILS...Low-lying areas of the Bitterroot Valley could
fall between 24 and 28 degrees.