Area Forecast Discussion
Issued by NWS Missoula, MT
Issued by NWS Missoula, MT
354 FXUS65 KMSO 050645 AFDMSO Area Forecast Discussion National Weather Service Missoula MT 1245 AM MDT Fri Jun 5 2026 .DISCUSSION... KEY MESSAGES: - Warm and dry today, breezy afternoon winds. - Showers, isolated thunderstorms, and cooler temperatures return this weekend. - Increasing potential for widespread precipitation by Wednesday and Thursday next week with a closed low pressure system. Today through Sunday: Deepening southwesterly flow aloft today will bring a gradual increase in mid- and high-level clouds. Daytime temperatures will climb to around 5 degrees above seasonal normals, accompanied by afternoon breezes gusting up to 20-25 mph. While conditions will remain pleasant for most outdoor activities, the combination of gusty winds and low afternoon relative humidity will lead to elevated fire weather conditions across Southwest Montana today and Saturday. Extreme caution should be taken with any open flames. On Saturday, a broad upper-level trough will settle into the Pacific Northwest, pushing a cold front through the Northern Rockies. Dynamic forcing and instability remain weak, keeping shower and thunderstorm coverage localized and primarily focused across northwest Montana and along the Continental Divide. Temperatures on Saturday will cool by roughly 10 degrees compared to today, with widespread wind gusts of 20-25 mph returning. As the core of the trough shifts overhead on Sunday, shower activity will become more widespread; however, total precipitation amounts are expected to remain light, generally under 0.20 inches. Snow levels do drop to around 5500 feet on Sunday with light accumulations of an inch or two, mainly south of I-90. Looking at overnight lows, the primary window for valley frost will be Monday morning as skies clear and winds calm behind the exiting system. Low temperatures are forecast to drop into the mid-to-upper 30s across many lower valley locations of western Montana and the higher valleys of north-central Idaho. Sunday morning will also need to be watched, but considerable cloud cover may limit frost development especially from I-90 southward. Regardless, gardeners should prepare to protect sensitive vegetation. Tuesday through next Friday: Attention turns to a large, closed upper-level low that ensemble clusters show settling over the western U.S. by mid-to- late next week. While notable variance remains regarding the exact depth, track, and speed of this trough, confidence is increasing for a significant, widespread precipitation event. The National Blend of Models (NBM) currently indicates a 60-80% probability of precipitation totals exceeding 0.50 inches across a large portion of the Northern Rockies. This system has the potential to bring significant moisture to the region, so please continue to monitor the forecast for updates. && .AVIATION...VFR conditions will prevail through the period. Deepening southwesterly flow ahead of an approaching Pacific trough will bring a gradual increase in high- and mid-level cloud cover today. As the surface pressure gradient tightens this afternoon, westerly winds will increase across the region, producing sustained speeds of 10-15 kts with gusts of 20-25 kts at most terminal sites. Winds will diminish after sunset, with VFR ceilings persisting overnight. && .MSO WATCHES/WARNINGS/ADVISORIES... MT...None. ID...None. && $$