textproduct: Great Falls

KEY MESSAGES

- Breezy to windy conditions continue this weekend through the middle of next week, with the most widespread and strongest winds expected late Sunday through early Tuesday.

- Temperatures trend towards unseasonably mild levels for most locations by early next week.

- Some cooling and mostly mountain snow looks to return for the second half of next week.

UPDATE

/Issued 801 PM MST Fri Jan 9 2026/

Two main changes with this update. The first involved the addition of precipitation chances along the Continental Divide. Light snow showers are expected to persist for a few more hours before tapering off by midnight. Additional snow amounts of 2 to 4 inches are possible along the highest peaks but no significant snowfall accumulations or impacts are expected at pass level and below.

The second change was to start the High Wind Warning along the Rocky Mountain Front now. Sustained winds near Dog Gun Lake have already reached 50 mph and other sites along the Rocky Mountain Front are starting to increase in wind speed faster than initially anticipated. No other additional changes to the warning were needed as the high winds are expected to remain contained within the current zones.

Otherwise, no changes were made to the going forecast. -thor

DISCUSSION

/Issued 801 PM MST Fri Jan 9 2026/

- Meteorological Overview:

Ridging and warmer air aloft moves in tonight and will generally shut down any lingering mountain snow and will bring warming temperatures and continued breezy to windy conditions this weekend through the middle of next week. West to northwesterly oriented jet streaks will move through the Northern Rockies and initially bring periods of strong winds along the Rocky Mountain Front this weekend. Then a shortwave will send the widest swath of 50 to 70 kt H700 flow into the forecast area and expend the stronger winds onto the plains and to a lesser degree to the southwest on Monday into Tuesday.

Aside from the winds, the most noteworthy characteristic of this pattern will be the strong ridge over the Pacific NW that will bring unseasonably mild temperatures and push afternoon highs as much as 15 to 30 degree above average Monday through Wednesday. Most ensembles favor this ridge retrograding westward off the Pacific coast during the second half of the week. This will shift the general flow aloft to a more northerly direction over the Northern Rockies and send at least a couple of fast moving troughs for modestly cooling temperatures and periods of mostly mountain snow. - RCG

- Forecast Confidence & Scenarios:

Periods of strong winds along the Rocky Mountain Front become more widespread on Monday...

The combination of stronger winds aloft, a tightening surface pressure gradient, and mountain wave activity will maintain wind speeds near high wind criteria (50 mph sustained/75 mph gusts) for both Saturday and Sunday. As of this writing, Saturday looks to be the day with the strongest winds given a slightly greater pressure gradient and better agreement for stronger winds by the latest hires guidance. A high wind warning was issued for the Rocky Mountain Front zones and will run from 10/09Z through 11/06Z. A stable layer may prevent the higher end winds from reaching the Cut Bank area for much of the time; however, the East Glacier County zone was also added to the warning given 70 to 80% confidence for 40 mph sustained winds over the western portion of the zone. Similar winds continue on Sunday though a slightly weaker surface pressure gradient and less agreement among hires members erodes forecast confidence for a high wind products at this time.

The strongest and most widespread winds arrive Sunday night into Monday. The Rocky Mountain Front will initially see winds increase Sunday night before expanding onto the plains on Monday. There are some uncertainties to deal with, including cloud cover limiting mixing, and the southern extent of the higher end winds. The central mountain ranges will be monitored for stronger winds should the H700 jet move/expand a little farther south. Also the end time is uncertain with some guidance maintaining strong winds aloft into the overnight hours and even into Tuesday. High wind watches were posted for the highest confidence areas, including the Rocky Mountain Front and most plains locations. The combination of the winds and unseasonably mild conditions does raise some grassland fire weather concerns, but extensive cloud cover should limit RHs from tanking to low and overall impacts should be on the low side. - RCG

AVIATION

10/06Z TAF Period

VFR conditions are expected to prevail through the TAF period with scattered to broken mid- to upper-level cloudiness across the region. LLWS will remain a concern through the period across central and north-central Montana with periods of mountain wave activity possible. -thor

PRELIMINARY POINT TEMPS/POPS

GTF 30 48 37 52 / 10 0 0 0 CTB 28 46 32 47 / 0 0 0 0 HLN 26 43 24 44 / 0 0 0 0 BZN 19 42 21 44 / 10 0 0 0 WYS 7 26 4 32 / 20 0 0 0 DLN 19 40 20 43 / 0 0 0 0 HVR 22 45 29 47 / 0 0 0 0 LWT 26 48 32 52 / 0 0 0 0

TFX WATCHES/WARNINGS/ADVISORIES

High Wind Warning until midnight MST Saturday night for East Glacier Park Region-Eastern Glacier, Western Toole, and Central Pondera-Northern High Plains-Southern High Plains.

High Wind Watch from Sunday evening through Monday evening for East Glacier Park Region-Northern High Plains-Southern High Plains-Southern Rocky Mountain Front.

High Wind Watch from Monday morning through Monday evening for Bears Paw Mountains and Southern Blaine-Cascade County below 5000ft-Eastern Glacier, Western Toole, and Central Pondera- Eastern Pondera and Eastern Teton-Eastern Toole and Liberty- Fergus County below 4500ft-Hill County-Judith Basin County and Judith Gap-Western and Central Chouteau County.