230 FXUS65 KTFX 231940 AFDTFXArea Forecast Discussion National Weather Service Great Falls MT 140 PM MDT Tue Sep 23 2025
.KEY MESSAGES...
- Remaining dry through the weekend.
- Mild temperatures persist through the weekend, with the two hottest days Wednesday and Thursday.
- Breezier period Thursday into Friday, mostly over the plains west of I-15.
&&
.DISCUSSION...
- Meteorological Overview:
A building upper level ridge across the region is allowing for a largely cloud free sky today, while allowing for temperatures to trend warmer. Ridging continues into Wednesday and much of Thursday, allowing for temperatures to climb another step those days while skies remain sunny.
Low amplitude troughing slides east southeast from off the BC coast toward the Northern Rockies toward the back end of Thursday, which will result in an increased zonal flow aloft. Breezy winds look to develop ahead of this troughing over the plains, with areas along the Rocky Mountain Front looking the most breezy.
As the base of the troughing passes across the region Thursday night, a cold front looks to move through. Temperatures heading into Friday look to drop a bit, but still be on the mild side, while winds shift to a more northwesterly direction. The wind shift and slight cool down are the two impacts from this troughing, as better support for any light precipitation looks to remain north in Canada.
Upper level ridging looks to become established once again behind the departing trough this weekend, promoting another dry and mild stretch. By early nest week an increasing share of ensemble members are favoring troughing off the Pacific coast, though there remains significant discrepancies on its east-west positioning. The further east this troughing sets up, the higher the likelihood for a cooldown and return of precipitation chances, while a further west solution would favor a warmer/drier stretch continuing. -AM
- Forecast Confidence & Scenarios:
Through Sunday the greatest uncertainty is with respect to wind strength Thursday into Friday. Deterministic guidance continues to favor strong cross barrier flow (H7 45-55 kts), particularly Thursday night. Although this is the case, the timing (Not well mixed) and lack of ridgetop stability both contribute to these stronger gusts not being efficiently translated to the surface. Hence, the chance for a 55+ mph gust along the Rocky Mountain Front and adjacent plains is overall quite low, peaking around 10 to 20% even in the most wind prone areas such as between Heart Butte and Browning, as well as between Browning and St Mary on US-89.
Heading into next week the main story will be tied to the placement of a developing trough off the Pacific NW coast as well as the timing and strength of the troughing as it eventually moves east toward the Northern Rockies. -AM
&&
.AVIATION... 23/18Z TAF Period
VFR conditions will prevail at all terminals across Southwest, Central, and North Central Montana through the 2318/2418 TAF period. Mountain obscuration is not expected over the next 24 hours. - Moldan
&&
.PRELIMINARY POINT TEMPS/POPS... GTF 49 87 45 87 / 0 0 0 0 CTB 45 84 40 82 / 0 0 0 0 HLN 45 84 48 85 / 0 0 0 0 BZN 40 80 43 82 / 0 0 0 0 WYS 28 70 29 72 / 0 0 0 0 DLN 38 79 41 81 / 0 0 0 0 HVR 45 85 44 84 / 0 0 0 0 LWT 45 84 46 83 / 0 0 0 0
&&
.TFX WATCHES/WARNINGS/ADVISORIES... None. &&
$$ http://www.weather.gov/greatfalls
NWS TFX Office Area Forecast Discussion