444
FXUS65 KTFX 082043
AFDTFX

Area Forecast Discussion
National Weather Service Great Falls MT
243 PM MDT Wed Oct 8 2025

.KEY MESSAGES...

 - It will be dry and mild through Friday.

 - Saturday through early next week it will cool down with primarily
   mountain snow and lower elevation rain across the area.

 - On Saturday it will be windy with showers across the area with
   thunderstorms in Central and Southwestern Montana.


&&

.DISCUSSION...

 - Meteorological Overview:

This afternoon there will be an upper level ridge over North
Central, Central, and Southwestern Montana. This will bring warm
temperatures (above seasonal averages) and dry weather to the area
this afternoon. However, this afternoon through this evening a quick
moving boundary will move through North Central Montana. On Thursday
the upper level ridge remains over North Central, Central, and
Southwestern Montana. On Thursday it will remain dry with above
seasonal averages for temperatures in Central and Southwestern
Montana and near seasonal averages for temperatures in North Central
Montana due to the boundary that moves through this afternoon
through this evening. On Friday the upper level ridge remains over
North Central, Central, and Southwestern Montana with an upper level
trough approaching Montana. Due to the upper level trough
approaching Montana there will be warm air advection from southerly
flow aloft which will bring well above seasonal average temperatures
and dry weather to North Central, Central, and Southwestern Montana
on Friday.

On Saturday the upper level trough moves over North Central,
Central, and Southwestern Montana combined with a surface cold front
that will move through Saturday afternoon and evening. On Saturday
due the strong surface pressure gradient, cold front, and strong
upper level flow it will be windy. On Saturday due to the upper
level trough combined with warm temperatures there will be enough
instability and shear to allow isolated thunderstorms to form in
Central and Southwestern Montana Saturday afternoon and evening.
Across North Central, Central, and Southwestern Montana there will
be isolated showers Saturday afternoon and evening. On Saturday
there will be anomalously high precipitable water (water available
in the air above Montana) which will lead to isolated
thunderstorms producing heavy rain. On Sunday the upper level
trough remains over North Central, Central, and Southwestern
Montana this combined with the cold front that moved through will
bring significantly colder temperatures, windy conditions, and
lower snow levels. There will be widespread precipitation
(primarily mountain snow and lower elevation rain) across North
Central, Central, and Southwestern Montana on Sunday. On Monday an
upper level ridge will build in briefly before an upper level
trough and surface cold front move through the area Monday
afternoon through Tuesday. This will bring mostly dry weather to
the area on Monday with more precipitation being brought to the
area with colder temperatures Monday night into Tuesday. IG

 - Forecast Confidence & Scenarios:

On Saturday there is a 15 to 30% chance for thunder south of the US
Highway 87/Montana Highway 200 between Great Falls and Lewistown. On
Saturday there is a 30 to 60% chance for wind gusts of 45 mph or
greater across the Rocky Mountain Front and adjacent plains. On
Saturday there is a 20 to 40% chance for wind gusts of 40 mph
across most of the rest of North Central, Central, and
Southwestern Montana. On Sunday there is a 30 to 60% chance for
wind gusts of 40 mph or greater across most of North Central,
Central, and Southwestern Montana.

Saturday morning through Monday morning across most of North
Central, Central, and Southwestern Montana there is a 35 to 70%
chance for a half inch of precipitation or greater. Saturday morning
through Monday morning there is a 30 to 70% chance for 6 inches of
snow or greater across the mountains of North Central, Central, and
Southwestern Montana. There is increasing confidence in lower
elevation snowfall sometime between the beginning to the middle of
next week due to good deterministic and ensemble model agreement. IG


&&

.AVIATION...
08/18Z TAF...VFR conditions prevail at all terminals through the
TAF period with mostly clear skies and light flow as upper level
high pressure sits squarely over Montana. The exception is at
KEKS, which is seeing southerly gusts around 30 kts this
afternoon, likely aided by nearby terrain. Surface flow out of the
south and southwest today veers more easterly overnight
especially along the Hi- Line... however this flow will remain
light overall. -Casey

&&

.PRELIMINARY POINT TEMPS/POPS...
GTF  36  63  37  75 /   0   0   0  10
CTB  33  60  33  68 /   0   0   0   0
HLN  38  68  39  77 /   0   0   0  20
BZN  35  73  38  76 /   0   0   0  10
WYS  25  67  33  64 /   0   0  10  40
DLN  34  71  39  72 /   0   0  10  10
HVR  36  68  38  75 /   0   0   0   0
LWT  39  67  41  76 /   0   0   0  10

&&

.TFX WATCHES/WARNINGS/ADVISORIES...
None.
&&

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