textproduct: Great Falls

KEY MESSAGES

- Warm, dry and breezy today. - Next weather system arrives Friday, bringing cooler temperatures along with some periods of rain/mountain snowfall. - Another weather system brings even cooler temperatures and more widespread precipitation to Montana, with more chances for mountain snowfall.

DISCUSSION

/Issued 215 AM MDT Thu Sep 10 2026/

- Meteorological Overview:

In the wake of a series of upper level systems earlier this week, a weak ridge embedded in northwesterly flow will continue to bring a period of warmer but breezy weather to North Central Montana today. This period of warmer weather will come to a quick end on Friday as a decaying upper level trough moves through Southern British Columbia and Alberta into Montana, which will bring cooler temperatures, along with some showers of rain and mountain snowfall as it pushes through. The cooler temperatures will linger behind this system, which will set up the next, stronger system to produce widespread precipitation with snow expected above 7000 feet, which would include some of the higher mountain passes.The unsettled weather pattern will continue into early next week, with continued chances for rain and mountain snowfall.

- Forecast Confidence & Scenarios:

Winds today: Westerly, cross barrier flow will bring some gusty winds to North Central and Southwestern Montana today. While winds are not expected to be strong enough to reach high wind criteria (58 mph for most, 75 mph along the Rocky Mountain Front), gusts to 35-50 mph will be possible across the area, especially along the Rocky Mountain Front and north slopes of the Little Belts, where winds will be strongest.

Mountain Snowfall this weekend: A strong upper level low will move into the Treasure State over the weekend, bringing well below average temperatures along with copious amounts of moisture. The cooler temperatures will bring snow levels down to 7000 feet above sea level, which will result in widespread mountain snowfall to areas above 7000 feet. Current forecasts keep snowfall amounts under 6 inches at the moment, but some of the highest terrain still have around a 10 percent chance of snowfall amounts over a foot over the weekend. Ludwig

AVIATION

10/12Z TAF Period

High confidence in VFR condition across all terminal through most of the TAF period, though some low clouds and light rain may begin to affect terminals after 6z. Breezy conditions will be the theme through much of the day especially across North Central Montana. Widespread wind gusts of 20-35kt are expected area wide, with terminals KCTB, KGTF, and KHVR likely seeing gusts on the upper end of that range. Winds will remain through the period, only lightening up around or shortly after 0z. -JR/Ludwig

For KGTF: Gusty winds will continue to be a concern through the day today, though winds should be fairly well aligned with runway 21 through 18z, after which winds will gradually shift to more of a westerly direction, which will result in crosswinds getting close to 15kts by 18z, then exceeding 15kts after 0z. Winds will then weaken overnight after 6z, at which point winds (and therefore crosswinds) will drop below 10kts. Ludwig

PRELIMINARY POINT TEMPS/POPS

GTF 81 48 59 43 / 0 80 60 10 CTB 73 42 54 39 / 0 50 80 10 HLN 84 50 68 46 / 0 70 60 0 BZN 84 48 73 44 / 0 0 10 10 WYS 72 36 72 31 / 0 0 10 0 DLN 82 46 77 40 / 0 0 0 0 HVR 82 45 64 38 / 0 40 70 0 LWT 84 45 60 39 / 0 50 90 20

TFX WATCHES/WARNINGS/ADVISORIES

Red Flag Warnings for Montana Fire Weather Zones 111 and 123 today.