textproduct: Great Falls

KEY MESSAGES

- Snow continues through late this afternoon across central and southwest Montana before winding down from northwest to southeast this evening.

- Gusty north winds creating areas of reduced visibility in blowing and drifting snow will continue through early this evening before gradually diminishing.

- Temperatures fall to the single digits above and below zero by Saturday morning with a colder airmass lingering across the area through the weekend.

UPDATE

/Issued 817 PM MST Fri Nov 28 2025/ An evening update to the forecast is out. Light snow continues to affect much of North Central MT this evening. The snow is slowly ending around Cut Bank, and then also in some of the valleys of Southwest MT, such as Dillon and Ennis. Overall, the upper level system producing the snow is moving off to our east, and the snow will gradually end from west to east overnight. New snow accumulations of 1/2 to 1 inch will be possible near I-15, while an inch or two will be possible further east in the Lewistown area.

The next set of advisories ends at 11 PM for the northwest portion of North Central MT. That should be ok...there will continue to be a few light snow showers after 11 PM, but the bulk of the impactful snowfall will be over with.

The main concern the rest of the night will be how cold it gets with clearing skies and does any fog develop towards daybreak. Otherwise, the next chance for snow after this system ends looks to be Tue into Wed. Brusda

DISCUSSION

/Issued 817 PM MST Fri Nov 28 2025/

- Meteorological Overview:

Snow continues across much of the area this afternoon from combined affects of a mid level shortwave moving across the area, north to northwesterly upslope flow and a low level frontal boundary moving southward across the region. The back edge of the shortwave is evident in satellite imagery moving into NW MT and reaching Glacier county this afternoon with precipitation expected to wind down from NW to SE across the area late this afternoon through this evening. The low level frontal boundary and cold airmass will surge through remaining portions of far southwest MT through the rest of this afternoon, bringing falling temperatures and gusty north winds, but only scattered precipitation to areas south of about Dillon to Ennis to Big Sky. North winds locally gusting as high as 30-40 mph will continue to produce at least localized drifting and blowing snow through early this evening before winds begin to subside from north to south across the area. Temperatures in the teens and twenties will fall to the single digits above/below zero tonight as the cold airmass and surface high pressure builds south across the area. Though winds diminish there will be enough to produce wind chill values as low as the single digits and teens below zero later this evening and overnight.

The cold airmass/surface high pressure remains centered across eastern MT and the Dakotas through the weekend before sliding off to the southeast Monday, maintaining the colder than average temperatures across the area with afternoon temps ranging from the teens and 20s across southwest MT to the single digits and low teens across the plains. Overnight minimum temps will generally be in the single digits above/below zero this weekend but as low as the teens below zero across portions of the Hi-line, where colder air will linger into Monday while areas to the southwest begin to moderate.

While temperatures moderate back to seasonal averages next week we remain in an unsettled northwesterly flow aloft. Model ensembles generally show another wave to move through the Northern Rockies around Tuesday but differ substantially with its eventual track and timing. This system will provide another opportunity for snow and likely will not be accompanied by significantly colder temperatures, but there is a fair amount of uncertainty still with details. Hoenisch

- Forecast Confidence & Scenarios:

Winter weather statements remain on track with the highest additional snowfall amounts likely to occur across areas that are enhanced by upslope N/NW flow, including the central MT mountain ranges and Bridger range and adjacent areas.

There is some potential for both overnight low temps and afternoon max temps to be lower than currently forecast in areas that received significant snow. Tomorrow's max temps were blended with the NBM 10th percentile to account for this. Hoenisch

AVIATION

29/06Z TAF Period

Snow is still winding down over the next few hours across the North-Central MT plains. This will continue to bring IFR/MVFR conditions. As snow clears overnight, MVFR ceilings will remain at KLWT and at KHVR until early Saturday morning. If clouds clear out over terminals overnight, then there is a slight risk for fog developing. So far, confidence is only high enough at KCTB and KHVR to mention in the TAFs. There's a slight chance a low stratus deck prevails over fog development. Expect tranquil conditions across the region Saturday afternoon. -Wilson.

PRELIMINARY POINT TEMPS/POPS

GTF 0 18 -2 20 / 100 0 0 0 CTB -9 9 -8 19 / 30 0 0 0 HLN 2 20 7 26 / 30 0 10 0 BZN -2 21 7 25 / 90 0 10 0 WYS -4 23 6 29 / 50 0 20 20 DLN 6 26 14 29 / 30 0 0 0 HVR -7 6 -15 6 / 80 0 0 0 LWT -3 18 -1 23 / 100 0 0 0

TFX WATCHES/WARNINGS/ADVISORIES

Winter Storm Warning until 11 PM MST this evening for Cascade County below 5000ft-Eastern Pondera and Eastern Teton-Eastern Toole and Liberty-Southern High Plains-Southern Rocky Mountain Front-Western and Central Chouteau County.

Winter Storm Warning until 5 AM MST Saturday for Bears Paw Mountains and Southern Blaine-Fergus County below 4500ft-Hill County-Northern Blaine County.

Winter Weather Advisory until 5 AM MST Saturday for Big Belt, Bridger and Castle Mountains-Elkhorn and Boulder Mountains- Gallatin Valley-Gates of the Mountains-Helena Valley-Judith Basin County and Judith Gap-Little Belt and Highwood Mountains- Meagher County Valleys-Snowy and Judith Mountains.