FXUS65 KMSO 101825 AFDMSO Area Forecast Discussion National Weather Service Missoula MT 1225 PM MDT Fri Apr 10 2026 .DISCUSSION... KEY MESSAGES: - Scattered showers and isolated thunderstorms begin this afternoon south of I-90, bringing a threat of sudden, gusty winds. - A weekend storm brings widespread rain and cooler temperatures. Light snow accumulations are possible over the highest terrain and Lost Trail Pass. - A much colder system arrives Wednesday into Thursday, bringing the potential for snow to fall down to the valley floors. Moisture will begin pushing into north-central Idaho and western Montana, primarily south of the I-90 corridor, this afternoon. Expect increasing clouds followed by scattered showers and a 15 percent chance of isolated thunderstorms over Lemhi, southern Idaho, and Ravalli counties heading into the evening. Because the air near the surface is currently very dry, rain falling from these initial showers will evaporate before hitting the ground. This can produce sudden, erratic wind gusts of 30 to 40 mph at the surface. A low-pressure system moves inland on Saturday, dragging abundant moisture into the Northern Rockies. Saturday afternoon will feature widespread showers and scattered thunderstorms as daytime temperatures peak. The highest chance for lightning (20 to 30 percent) will be across western Idaho and Clearwater counties, and into west-central Montana. The strongest storms could produce brief heavy rain and gusty winds. By Sunday, the system transitions into a widespread precipitation event as cooler air begins filtering into the region. While temperatures will cool, snow will largely be confined to the higher terrain. Travel impacts this weekend should be minimal, though some light, slushy accumulations are possible over Lost Trail Pass. Monday through Thursday: Unsettled weather continues on Monday with valley rain and high-elevation mountain snow. However, the main focus for next week is a strong cold front slated to arrive Wednesday into Thursday. This system will bring a significant drop in temperatures, with current forecasts showing snow levels plummeting to 1500-2000 feet by Thursday morning. This introduces the potential for snow to fall all the way down to the valley floors. There is still considerable uncertainty regarding the exact details of this Wednesday-Thursday system. The primary unknown is how much moisture will still be around when the coldest air arrives. If the moisture is pushed out quickly by the front, valley snow accumulations will be minimal. If the cold air and moisture overlap perfectly, we could see accumulating valley snow and more widespread travel impacts. We will be monitoring this closely over the coming days. .AVIATION... VFR conditions will prevail for most terminals early this afternoon. High clouds will continue to thicken and stream in from south to north. Shower activity will follow, bringing roughly a 30 percent chance for showers at KSMN and KHRF starting around 2200Z and lasting through the overnight hours. A very dry lower atmosphere will be highly conducive to sudden, gusty, and erratic winds accompanying any shower or thunderstorm activity late today into tonight. && .MSO WATCHES/WARNINGS/ADVISORIES... MT...None. ID...None. && $$