439
FXUS65 KTFX 180113
AFDTFX

Area Forecast Discussion
National Weather Service Great Falls MT
713 PM MDT Sat Oct 17 2026

.KEY MESSAGES...

 - Strong winds along the Rocky Mountain Front and nearby plains
   will continue to slowly diminish through midnight.

 - Temperatures will fluctuate over the next few days ranging
   between near normal on Sunday and Tuesday to around 10 degrees
   above normal on Monday and Wednesday.

 - Overall dry conditions are expected through Monday, with low
   chances for precipitation arriving on Tuesday across Southwest
   and Central Montana.

&&

.UPDATE...

Winds are slowly decreasing along the Rocky Mountain Front and
adjacent plains this evening with the loss the diurnal heating.
The Sweetgrass Hills zone was dropped from the warning with this
update and the wind speeds for the zones still in the warning were
lowered per current observations. The remaining warnings should
be ready for cancellation within the next couple of hours. - RCG

&&

.DISCUSSION...
/Issued 303 PM MDT Sat Oct 17 2026/

 - Meteorological Overview:

Upper level ridging over the Western CONUS early this morning will
continue to be flattened as a potent shortwave over the Gulf of
Alaska slides east over British Columbia and the Canadian Prairie
Provinces through the day today. Increasing cross barrier flow over
the Northern Rockies will lead to strengthening southwest to west
winds across Southwest through North Central Montana, most notably
along the Rocky Mountain Front and International Border. These
downsloping southwest to west winds will lead to another day of
above normal temperatures across the region, with highs peaking in
the mid-60s to near 70 degrees in the valleys of Southwest and
Central Montana to the low 70s to near 80 degrees over the plains of
Central and North Central Montana.  "Cooler" temperatures are then
expected into the day on Sunday in wake of a weak Pacific front,
which will slide east and over the Northern Rockies late tonight,
with highs topping out in the upper 50s to low 60s. Despite
persistent zonal flow over the Northern Rockies on Sunday weak
surface high pressure settling in over the Pacific Northwest and
Northern Rockies will help to support light surfaces winds and
continued dry conditions. - Moldan

Through next week split flow will set up with an upper-level low
centered off the coast of California. This setup will put Montana
under southwesterly flow with moisture being funnel into
Southwest Montana for daily precipitation chances. The forecast
uncertainty increases significantly towards late next week with
some hints that an upper-level trough could move south and merge
with the low as it moves off to the northeast. This could bring
more widespread chances for precipitation and some cooler
temperatures although there is still a bit of disagreement on what
exactly this means for our area.  -thor


 - Forecast Confidence & Scenarios:

Gusty to strong winds will continue across Central and North-
Central Montana through the rest of the afternoon and evening
hours. The strongest winds will be more confined to the Rocky
Mountain Front where sustained winds of 40 to 50 mph and gusts up
to 85 mph are possible.

While frequent gusts in the 40s are occurring across the Northern
Plains and a gust up to 50 mph has been observed in Great Falls,
there is still low confidence in wind speeds/gusts reaching full
high wind criteria. As a result, no expansion was made to the High
Wind Warning with this forecast.

Winds will start to taper off towards sunset into the overnight
hours. Periods of gusty winds may still continue for a little
while but generally the worst of the winds are expected to be done
by 8 PM.  -thor


&&

.AVIATION...
18/00Z TAF Period

VFR Conditions prevail through the TAF period. Gusty winds will
begin to wane through the evening and overnight hours, largely
falling below 10kts by 18/06z. Conditions will remain calm
through the remainder of the TAF period with mountain wave
activity also waning through the night. -JR

&&

.PRELIMINARY POINT TEMPS/POPS...
GTF  42  60  39  69 /   0   0   0   0
CTB  36  57  32  60 /   0   0   0   0
HLN  37  62  35  67 /   0   0   0   0
BZN  34  60  32  66 /   0   0   0   0
WYS  23  57  22  58 /   0   0   0   0
DLN  33  61  33  64 /   0   0   0   0
HVR  38  62  35  65 /   0   0   0   0
LWT  40  57  37  71 /   0   0   0   0

&&

.TFX WATCHES/WARNINGS/ADVISORIES...
High Wind Warning until midnight MDT tonight for East Glacier
Park Region-Northern High Plains-Southern High Plains-Southern
Rocky Mountain Front.

&&

$$
http://www.weather.gov/greatfalls