textproduct: Great Falls

KEY MESSAGES

- Temperatures gradually rise over the weekend and into next week. - Snow Saturday will be a bit heavier, but still only 2 to 4 inches in the Little Belt Mountains. - Warm, dry, and generally benign weather expected next week.

UPDATE

Surface high pressure continues to shift away from the region, presently across the eastern Dakotas and into Minnesota. Given this, at least some cloud cover moving in this evening, and weak downsloping winds developing across most of the plains through the night, overnight temperatures and associated wind chills do not look be as cold tonight as last night in most areas.

The exception to this looks to be around Fergus county, where ambient temperatures have already fallen to less than 10 below. Even a light wind will result in a wind chill of -25 F or colder in these temperatures. A Cold Weather Advisory was issued for this area through the overnight. Approaching cloud cover should help temperatures rise somewhat later tonight, but enough of a window exists through the evening that the advisory was warranted.

A slowly weakening upper jet and a mid level shortwave diving southward within a cyclonic flow aloft will support some mainly light snow across the region Saturday into Saturday night. Although forcing looks to be on the weaker side, along with a DGZ that largely looks to be shallow, respectable QPF near the Little Belts will support at least a few inches of snow beginning Saturday morning, persisting into at least the early overnight hours. Should confidence in higher snow amounts increase, a Winter Weather Advisory for the Little Belts may become necessary. -AM

DISCUSSION

/Issued 450 PM MST Fri Jan 23 2026/

- Meteorological Overview:

Light southerly surface flow will develop later this evening and overnight tonight, which will help to bring some marginally warmer air back into the area this evening and overnight tonight. In addition to the light southerly winds, clouds moving in from the north overnight tonight will help insulate us as well, which will keep temperatures from falling as far as they did last night.

Our next shortwave surges southward and brings another round of light snow and gusty north to northwesterly winds Saturday into Sunday. This will also serve to reinforce the Arctic air in place, though overall temperatures will be slightly milder than today.

The northwesterly flow aloft remains in place heading into next week, but the temperatures aloft warm markedly and the shortwaves passing through will be more subtle. This will result breezy and dry conditons with temperatures warming well above average for most locations by mid-week. The notable exception to this will be for the normally cooler Milk River Valley where the shallow cold air will hang on a bit longer than other areas.

Moist ensembles bring in another trough moving into the interior west towards the end of the workweek, but there are disagreements on whether the main circulation stays over the northern tier or if it splits off and dives southward into the great Basin and desert southwest. The former solution would result in a brief period with below average temperatures, mostly for northern areas, and another round of light snow. Should the energy move south, then drier and milder conditions will prevail. - RCG/Ludwig

- Forecast Confidence & Scenarios:

Arctic chill through Saturday morning...

Temperatures will once again fall later this evening and overnight. However, increasing cloud cover and slight warming aloft later this evening may result in a shorter period with wind chills falling into the -15 to -25F range.

Light snow Saturday into early Sunday...

Our next round of snowfall arrives Saturday through Sunday. Both deterministic and probabilistic guidance are highlighting generally light snowfall totals with this upcoming system, though some more appreciable snowfall is expected in the Little Belt/Snowy Mountains and their northerly upslope foothills. Probabilities are round 50% for a 2 to 4 inch snowfall over the higher terrain and around an inch or so over the nearby hills and plains. - RCG/Ludwig

AVIATION

24/00Z TAF Period

Snow and MVFR clouds are currently clearing up across the Southwest MT, however, MVFR ceilings will linger at KEKS for a little longer this evening. Otherwise, VFR conditions prevail for the evening. A light snow band is expected to set up early Saturday morning across North-Central MT, sliding to the south throughout the day. Here, this will bring MVFR to IFR conditions. Winds will also turn northwesterly with the frontal passage late morning through afternoon. -Wilson

PRELIMINARY POINT TEMPS/POPS

GTF -6 24 0 26 / 10 40 60 0 CTB -7 20 -7 25 / 20 40 30 0 HLN 1 24 4 24 / 10 20 50 0 BZN -1 23 4 21 / 0 20 30 0 WYS -16 17 -6 18 / 0 10 30 10 DLN 1 27 6 27 / 0 0 10 0 HVR -6 15 -11 14 / 10 30 10 0 LWT -15 19 -6 19 / 10 60 70 10

TFX WATCHES/WARNINGS/ADVISORIES

Cold Weather Advisory until 9 AM MST Saturday for Fergus County below 4500ft-Snowy and Judith Mountains.