textproduct: Great Falls

KEY MESSAGES

- It will be warmer and dry through the New Year's Day

- Mostly light mountain snow returns Thursday evening, with daily chances of light mountain snow through the beginning of next week.

- Windy condtions return to the Rocky Mountain Front this weekend.

DISCUSSION

/Issued 1155 PM MST Tue Dec 30 2025/

- Meteorological Overview:

Winds along the Rocky Mountain Front will be peaking over he next hour. After that, the pressure gradient decreasing along the Rocky Mountain Front overnight will decrease winds. Though, winds will still remain relatively breezy through the work week. An upper-level ridge will keeps things dry through the day Thursday with above average temperatures for most of the region. A backdoor cold front swinging through the Hi-line Wednesday and Thursday will keep temperatures closer to average up there.

Thursday evening and Friday, the upper level ridge begins to break down as a trough builds along the West coast. A shortwave will bring light mountain snow to Southwest MT Thursday evening through Friday, slowly lifting north throughout the timeframe. With the troughing being the dominant pattern through the beginning of next week, a few waves of light mountain snow and low end chances for precipitation at lower elevations. The ridge breakdown will also bring in better upper-level flow and bring back windy conditions to the Rocky Mountain front with breezy winds across the rest of the region. Above normal temperatures will continue into the beginning of next week as well.

- Forecast Confidence & Scenarios:

Although this is a lower confident scenario (<20% chance), forecast soundings indicate the slight possibility of there being enough low level moisture for patchy freezing drizzle overnight Thursday into Friday morning along the Hi-line/backdoor cold front. However, models aren't that confident in precipitation developing that far north yet, and there is a good chance it remains a low cloud deck instead.

There seems to be good model agreement that the snow will be light in the mountains through the weekend. There's a 10-30% chance for 2" of snow each day Friday through Monday. The best chances for any precipitation to move off of the mountains will be into the Southwest MT Valleys. Even then, there is only a less than 40% chance for 0.05" of precipitation through Monday.

For winds this weekend, ensembles don't seem the most excited about the winds. There is a 20-50% chance for 58 mph winds along the immediate eastern slopes of the Rocky Mountain Front Saturday and Sunday, with a 20-50% chance for 35 mph winds elsewhere. -Wilson

AVIATION

31/12Z TAF Period

Broken mid- to upper level cloudiness will persist in lee of the Continental Divide across Central and North Central Montana through 03-06z Thursday as a Chinook Arch remains nearly stationary. Mountain wave turbulence is expected near this feature, especially west of the US Hwy 89 corridor. Otherwise VFR conditions are expected across all terminals, but low clouds will begin to move southeast towards the KHVR terminal near 12z Thursday. - Moldan

PRELIMINARY POINT TEMPS/POPS

GTF 49 29 45 31 / 0 0 0 10 CTB 45 22 40 23 / 0 0 0 0 HLN 42 24 42 28 / 0 0 0 10 BZN 43 22 43 28 / 0 0 0 10 WYS 38 11 35 23 / 0 0 30 50 DLN 45 25 42 30 / 0 0 10 10 HVR 34 16 28 15 / 0 0 0 0 LWT 50 30 47 29 / 0 0 0 0

TFX WATCHES/WARNINGS/ADVISORIES

None.