textproduct: Missoula

WHAT HAS CHANGED

Lower snow levels along I-90 and Highway 200 corridors and northern Clearwater County, with higher snow amounts than previously forecast.

DISCUSSION

Surface observations and webcams reveal snow levels falling quicker than forecast, with snow being reported down to 3,000-3,500 feet in the northern Clearwater Mountains near Pierce, ID and east of Lookout Pass in Montana. Snow is also being observed north and east of Missoula on US-93 over Evaro Hill and on Highway 200 east near Greenough. Given recent observation and model trends, the forecast has been adjusted to lower snow levels along the I-90 and Highway 200 corridors, with higher forecast snow amounts through Tuesday morning. The highest valley snow totals will focus east of Missoula on Highway 200 and I-90, with generally 2-6 inches, with areas west of Missoula on I-90 seeing 2-5 inches. In Missoula, rain will transition to snow overnight, with warm ground temperatures limiting snow accumulations to grassy and elevated surfaces. Given the wet nature of snow, snow loading may lead to isolated power outages.

AVIATION

Ceilings and visibility reductions will become more common overnight Pacific moisture leads to widespread precipitation and lowering snow levels, along and north of the I-90 corridor. Rain will transition to a wet snow overnight in Missoula, with a 50% chance of IFR/LIFR visibilities by 25/0900Z. Warm ground temperatures will generally limit runaway accumulations, with air temperatures near 31-32F by Tuesday morning.

PREV DISCUSSION

/ISSUED 158 PM MST Mon Feb 23 2026/

DISCUSSION...

KEY MESSAGES:

- Winter Weather Advisories Expanded: New advisories are in effect for the Bitterroot/Sapphire Mountains, Potomac/Seeley Lake Region, and northern portions of the Butte/Blackfoot Region as rain transitions to snow.

- Widespread Valley Rain & Slush: Most valleys will transition to rain or a messy rain/snow mix this evening and overnight, leading to ponding on roads and localized slushy accumulations.

- Colder Midweek Transition: A cold front Tuesday night will bring a return to all snow for the valleys along with gusty winds and quick-hitting snow showers on Wednesday.

A potent moisture plume is currently impacting the region. We have expanded Winter Weather Advisories to include the Bitterroot/Sapphire Mountains, Potomac/Seeley Lake Region, and the northern Butte/Blackfoot Region.

Mountains: Heavy snow will continue through tonight. Expect travel difficulties over Lookout, Marias, Lolo, Lost Trail, and MacDonald Passes.

Valleys: Temperatures have again warmed enough for most valleys to see mainly rain showers into this evening. Confidence is medium regarding the timing of the snow-to- rain transition in the Seeley Lake/Potomac/Blackfoot areas late this evening.

Winds: Southwesterly winds will gust between 20-30 mph for most areas, with higher gusts near 40 mph possible around Butte and across ridge tops.

The region remains in a warm southwesterly flow for much of the day on Tuesday. Snow levels will rise to between 4,500 and 5,500 feet during the afternoon, keeping the steady snow restricted to the mountains while valleys experience occasional rain showers. However, conditions will change rapidly Tuesday night.

A cold front will sweep through late Tuesday. Rain will transition back to snow for most elevations by Wednesday morning. We continue to watch the potential for snow bands or squalls Tuesday evening through Wednesday. These can cause sudden drops in visibility and rapid snow accumulation on roads over short distances. The latest trends suggest that the snow bands will focus south of I-90.

Westerly winds will turn gusty behind the front with 30-40 mph winds gusts common on Wednesday.

Thursday/Friday: Expect scattered snow showers, primarily focused on the mountains. Breezy winds will continue, and temperatures will be near seasonal averages.

Next Weekend: Forecast models show a weak disturbance arriving on Saturday. While not a major storm, it will likely keep light snow chances in the forecast through the end of February.

AVIATION...Breezy conditions today with gusts 20 to 30 kts at area terminals. Clouds will increase and lower through the day. Initially most shower activity will be in the vicinity of terminals but as valleys moisten up, they will overcome the effects of downsloping. Expect precipitation this evening to bring lowered ceilings and after transitioning to snow lowered visibilities at times.

MSO WATCHES/WARNINGS/ADVISORIES

MT...Winter Weather Advisory until 5 AM MST Tuesday for West Glacier Region.

Winter Weather Advisory until 11 AM MST Tuesday for Bitterroot/Sapphire Mountains...Lower Clark Fork Region.

Winter Weather Advisory until 11 AM MST Tuesday for Butte/Blackfoot Region.

Winter Weather Advisory until 11 AM MST Tuesday for Potomac/Seeley Lake Region.

ID...None.