textproduct: Great Falls

KEY MESSAGES

- Warm and dry conditions are expected through Friday.

- Warm, breezy, and dry conditions will bring elevated fire weather conditions.

- There will be a shift to cooler and wetter snow for the weekend, with mountain snow and rain/snow at lower elevations.

DISCUSSION

/Issued 1153 PM MDT Tue Oct 6 2026/

- Meteorological Overview:

Upper-level ridging in the region will continue to dominate through Friday, which will continue the warm and dry pattern through then. Temperatures will remain well above normal through Friday, with temperatures peaking again on Friday. Starting Friday, the next incoming trough will begin to drive south out of Canada, increasing west to southwest flow aloft. The ridge breakdown will also bring in a mid level jet. This jet coinciding with daytime heating will mix these winds down to the surface. As a result breezy to gusty winds are forecasted for Friday.

The trough and with the cold front starts to push south into Montana by early Saturday, bringing the start to decreasing temperatures and precipitation. The trough continues to dig south throughout the weekend and into Monday, which will keep the cooling trend with mountain snow and rain/snow at lower elevations. The coldest lows will be Monday morning. There remain model variability in timing and snow amounts still.

- Forecast Confidence & Scenarios:

Confidence is increasing for cold temperatures and mountain snow Saturday through Monday. Models have snow levels falling behind the cold front throughout the day Saturday, with the best push for colder air aloft moving through Saturday night into Sunday morning. There will be a good drop in temperatures (up to 20 to 30 degrees) Friday with lower elevation highs forecasted in the 30s to 40s Sunday.

Models have been trending towards a splitting trough solution in the most recent runs. This has the trough digging and splitting off the cut off low farther to the south by California. This trend as a result, has been decreasing the snow amounts a little bit, keeping most of the snow in the mountains. With lower elevations forecasted to drop below freezing Saturday night into Sunday morning, that will allow for some snow to fall. There remains a 40-70% chance for 2" of snow to fall across the Southwest Valleys, the Highway 200 corridor, and the Rocky Mountain Front. With this being a marginal temperature snow event, there is a question on how much snow accumulates at first with an initially warm ground/road pavement.

For the mountains, models have been trending the North-Central Continental Divide and the Little/Big Belts to receive the highest amounts. Lee troughing behind the front help keep snow there as well as the front stalling by Southwest MT mountains Saturday, allowing a convergence zone to set up. There remains some uncertainty in how much snow falls along these zones but there is a 40-70% chance for 9" of snow for Kings Hill, Rogers and Marias Pass. There may be some melting of snow on these passes before moderate snow rates crash surface temperatures. The snow will be wet and heavier, which can also weigh down power lines/trees.

I would like to see some more consistency before hopping onto a solution so we will continue to monitor on how things trend leading to the event. -Wilson

AVIATION

07/12Z TAF Period.

VFR conditions prevail through the TAF period with light surface winds and scattered to broken high level clouds streaming across mainly north-central/central MT. Hoenisch

FIRE WEATHER

Continued dryness and above normal temperatures combined with moderate to poorer overnight recoveries are expected through Friday. This will help continue to dry out fuels throughout the week. The ridge breakdown Friday brings an increase in winds, exceeding 40 mph in some areas. Therefore, the dry, warm, and breezy conditions bring elevated fire weather conditions Friday before the cool down and precipitation for the weekend. -Wilson

PRELIMINARY POINT TEMPS/POPS

GTF 72 43 77 51 / 0 0 0 0 CTB 67 40 73 48 / 0 0 0 0 HLN 77 42 78 46 / 0 0 0 0 BZN 76 40 76 41 / 0 0 0 0 WYS 73 31 72 31 / 0 0 0 0 DLN 78 41 77 41 / 0 0 0 0 HVR 71 36 73 44 / 0 0 0 0 LWT 73 44 75 49 / 0 0 0 0

TFX WATCHES/WARNINGS/ADVISORIES

None.