Yellowstone National Park, Wyoming

Regional Weather Alerts


     

Alert: Frost Advisory
Area(s): Missoula/Bitterroot Valleys
Effective: 2026-05-18 @ 1:00 pm -> 2026-05-19 @ 10:00 am
Onset: 2026-05-19 @ 1:00 am -> 2026-05-19 @ 10:00 am
Severity: Minor
Certainty: Likely
Urgency: Expected
Issued By: NWS Missoula MT on 2026-05-18 @ 1:00 pm
Headline: Frost Advisory issued May 18 at 12:00PM MDT until May 19 at 9:00AM MDT by NWS Missoula MT
Description: * WHAT...Temperature ranges between 27 and 32 will result in frost
formation.

* WHERE...Low-lying areas of the Missoula and Bitterroot Valleys.

* WHEN...From midnight tonight to 9 AM MDT Tuesday.

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

Alert: Frost Advisory
Area(s): Flathead/Mission Valleys
Effective: 2026-05-18 @ 1:00 pm -> 2026-05-19 @ 10:00 am
Onset: 2026-05-19 @ 1:00 am -> 2026-05-19 @ 10:00 am
Severity: Minor
Certainty: Likely
Urgency: Expected
Issued By: NWS Missoula MT on 2026-05-18 @ 1:00 pm
Headline: Frost Advisory issued May 18 at 12:00PM MDT until May 19 at 9:00AM MDT by NWS Missoula MT
Description: * WHAT...Temperature ranges between 30 and 32 will result in frost
formation.

* WHERE...Flathead/Mission Valleys.

* WHEN...From midnight tonight to 9 AM MDT Tuesday.

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

* ADDITIONAL DETAILS...Temperature ranges: 32 to 37 degrees in the
Flathead Valley, and 30 to 35 in the Mission Valley.

Alert: Frost Advisory
Area(s): Lower Clark Fork Region
Effective: 2026-05-18 @ 1:00 pm -> 2026-05-19 @ 10:00 am
Onset: 2026-05-19 @ 1:00 am -> 2026-05-19 @ 10:00 am
Severity: Minor
Certainty: Likely
Urgency: Expected
Issued By: NWS Missoula MT on 2026-05-18 @ 1:00 pm
Headline: Frost Advisory issued May 18 at 12:00PM MDT until May 19 at 9:00AM MDT by NWS Missoula MT
Description: * WHAT...Temperatures ranging between 27 and 34 will result in frost
formation.

* WHERE...Lower Clark Fork Region, but not along Highway 200 west of
Trout Creek.

* WHEN...From midnight tonight to 9 AM MDT Tuesday.

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

* ADDITIONAL DETAILS...Temperature ranges: 31 to 36 degrees Trout
Creek to Plains and including Evaro, 31 to 35 Alberton, 33 to 35
Superior, 30 to 32 St. Regis, and 27 to 29 DeBorgia to Haugan.

Alert: Frost Advisory
Area(s): Bitterroot/Sapphire Mountains
Effective: 2026-05-18 @ 1:00 pm -> 2026-05-19 @ 10:00 am
Onset: 2026-05-19 @ 1:00 am -> 2026-05-19 @ 10:00 am
Severity: Minor
Certainty: Likely
Urgency: Expected
Issued By: NWS Missoula MT on 2026-05-18 @ 1:00 pm
Headline: Frost Advisory issued May 18 at 12:00PM MDT until May 19 at 9:00AM MDT by NWS Missoula MT
Description: * WHAT...Temperature ranges between 25 and 32 will result in frost
formation.

* WHERE...Bitterroot/Sapphire Mountains.

* WHEN...From midnight tonight to 9 AM MDT Tuesday.

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

* ADDITIONAL DETAILS...Temperature Ranges: 30 to 32 along US-12 west
of Lolo, 26 to 29 degrees in the Rock Creek area, 26 to 28 Sula,
and 25 to 28 in the Painted Rocks area.