textproduct: Great Falls

KEY MESSAGES

- Low wind chills through the morning hours today across North Central Montana.

- Temperatures moderate through the first half of the work week outside of the cold prone valleys.

- Gusty west winds along the Rocky Mountain Front through Wednesday, with the potential for blowing/drifting snow today and tonight.

UPDATE

/Issued 957 AM MST Sun Dec 28 2025/

Main update this morning was to cool temperatures in the Southwestern Valleys, as they are likely to struggle to warm through the day today after being colder than expected early this morning. Ludwig

DISCUSSION

/Issued 957 AM MST Sun Dec 28 2025/

- Meteorological Overview:

Upper level ridging over the Eastern Pacific/Pacific Northwest early this morning will amplify and gradually build eastward towards the Northern Rockies through the middle of the work week, with predominately dry, northwest flow being in place over Southwest through North Central Montana for the period. This pattern will lead to a moderating and overall dry trend for all elevations, with periods of gusty winds along the Rocky Mountain Front, Montana Hwy 200 corridor, and in the north-south orientated valleys in Southwest Montana. By the second half of the work week the upper level ridge axis will begin to slide east and over the Northern Rockies, with continued near to above normal temperatures and dry conditions outside of the mountains. - Moldan

- Forecast Confidence & Scenarios:

Gusty West Winds through the Middle of the Work Week...

A moderate to strong pressure gradient orientated along the Rocky Mountain Front will help to support gusty west winds from the late morning hours on Sunday through at least Wednesday afternoon. While these gusty winds will lead to warming temperatures through the period the initial onset of the winds from today through tonight will likely lead to patchy blowing/drifting snow, mainly west of the US Hwy 89 corridor from a Dupuyer to Heart Butte line points north. Given the limited snow depth across this region a Winter Weather Advisory for blowing snow was not issued, but motorist should be prepared for areas of limited visibility (especially in the foothills) and the potential for minor drifts on roadways. NBM4.3 probabilities support between a a 40-70% chance for wind gusts in excess of 55 mph from today through Tuesday for areas west of the US Hwy 89 corridor, and a 30-55% chance for gusts in excess of 55 mph on Wednesday.

Warming Temperatures through the First Half of the Work Week...

Confidence is high that temperatures will begin to moderate to within 10-15 degrees of normal today and near to above normal by Monday across much of North Central, Central, and Southwest Montana. The exception of the this warming trend will be the cold prone valleys in Southwest and Central Montana (i.e. Gallatin and Helena Valleys) and the Milk River Valley in North Central Montana where the shallow cold air will be stubborn to mix out. These locations are likely to remain well below normal through at least Monday, with the Helena and Gallatin Valleys likely mixing out on Tuesday and rebounding back above normal. For the Milk River Valley there will be a short window for temperatures to moderate late Tuesday afternoon before a weak backdoor cold front pushes into the area Tuesday night/Wednesday morning. - Moldan

AVIATION

28/18Z TAF Period

VFR conditions prevail at TAF sites over the next 24 hours. The only concern will be for localized instances of blowing snow along the Rocky Mountain Front given recent snowfall and gusty winds that will persist through the TAF period. -AM

PRELIMINARY POINT TEMPS/POPS

GTF 25 22 38 27 / 0 0 0 0 CTB 21 18 32 25 / 0 0 0 0 HLN 18 12 29 23 / 0 10 10 0 BZN 17 6 23 18 / 0 0 10 0 WYS 13 -9 17 4 / 0 10 10 0 DLN 17 8 27 18 / 0 0 0 0 HVR 1 -2 19 18 / 0 0 0 0 LWT 20 10 38 26 / 0 0 0 0

TFX WATCHES/WARNINGS/ADVISORIES

Cold Weather Advisory until 11 AM MST this morning for Eastern Glacier, Western Toole, and Central Pondera-Eastern Toole and Liberty-Fergus County below 4500ft-Snowy and Judith Mountains.

Extreme Cold Warning until 11 AM MST this morning for Bears Paw Mountains and Southern Blaine-Hill County-Northern Blaine County.