textproduct: Great Falls

KEY MESSAGES

- Gusty to locally strong north to northwest winds this morning across eastern portions of north-central Montana will gradually diminish through this afternoon.

- A colder airmass expands across the area Thursday and Friday with the greatest risk for subzero temperatures and wind chills across the north-central Montana plains Thursday night through Friday morning.

- Some very light snow or flurries are possible as the cold air moves into the region Thursday and Thursday night with additional opportunities for mainly light snow as temperatures moderate this weekend.

DISCUSSION

/Issued 353 AM MST Wed Jan 21 2026/

- Meteorological Overview:

The area remains under a cyclonic north to northwest flow aloft on the western periphery of a deep/large scale upper level trough. An embedded shortwave perturbation is rippling across central/eastern MT this morning, bringing another period of gusty N/NW surface winds to noth-central MT. Locally strong gusts continue through this morning mainly across portions of Blaine and Fergus counties as a low level wind maximum (50kts at 850mb) zips across these areas in association with the shortwave. Except for an increase in lower to mid level clouds and perhaps a few morning flurries across eastern portions of north-central MT, mainly dry conditions are expected today as slightly cooler airmass continues to filter in from the north with temperatures a few degrees cooler than yesterday. The center of the deep Canadian upper trough rotates from Hudson Bay across southern Manitoba and Ontario Thursday and Friday with a strong (~1050mb) surface high pivoting around its west side from the Canadian prairies to the Dakotas. While the core of this cold airmass remains well to the east, colder air will expand across the area Thursday into Friday with areas on the plains and particularly Hill and Blaine counties seeing the coldest conditions and lowest temperatures occurring Friday morning. As the cold air expands/deepens across the plains late Thursday and Thursday night, there may be enough low level moisture to wring out some very light snow or flurries, especially where low level N/NE upslope flow impinges on the central MT mountain ranges and Rocky Mtn Front.

Looking ahead to the weekend, the colder air recedes as the strong surface high pivots away from the area and upper troughing shifts further east. A general NW flow aloft looks to persist however with longer range models/ensembles keeping an upper level ridge axis west of the area. There remains a fair amount of uncertainty in the details of energy within the NW flow this weekend into early next week with some potential for additional disturbances to bring some opportunities for light snow, but with low confidence in timing for now. Hoenisch

- Forecast Confidence & Scenarios:

The colder airmass expanding into the region on Thursday will be deepest across the north-central MT plains, where temperatures will fall to the single digits above/below zero Thursday night and potentially as low as the teens below zero across Hill and Blaine counties. The probability for minimum temps of 10 below zero or colder Friday morning ranges from around 50-60% for areas from Cut Bank to Great Falls and Lewistown to 80% or higher across Hill and Blaine counties. Strong surface high pressure centered east of the area will likely provide enough wind (10-15 mph) to support wind chills as low as 15 below to 20 below across portions of north- central MT with a 60-80% risk of 20-30 below zero wind chills across Hill and Blaine counties. Cold advisory statements are likely for portions of north-central MT for the Thursday night period. Hoenisch

AVIATION

21/12Z TAF Period

Gusty north/northwest surface winds primarily affecting eastern portions of north-central MT this morning (KHVR, KLWT) will gradually subside this afternoon. Lower (mainly VFR) cloud ceilings will increase for a period this morning along with areas of mountain obscuration. There is a low (20-30%) probability for a period of MVFR cloud cigs this morning at KLWT and KGTF. Hoenisch

PRELIMINARY POINT TEMPS/POPS

GTF 30 11 20 -3 / 0 0 20 20 CTB 27 5 14 -8 / 0 0 20 20 HLN 31 11 23 2 / 0 0 0 10 BZN 31 10 25 2 / 0 0 0 10 WYS 26 -2 26 -4 / 0 0 0 10 DLN 35 14 30 7 / 0 0 0 0 HVR 26 1 10 -15 / 0 0 10 10 LWT 26 6 16 -7 / 10 0 10 20

TFX WATCHES/WARNINGS/ADVISORIES

High Wind Warning until 8 AM MST this morning for Bears Paw Mountains and Southern Blaine-Eastern Toole and Liberty-Fergus County below 4500ft-Northern Blaine County.