046
FXUS65 KTFX 250830
AFDTFX

Area Forecast Discussion
National Weather Service Great Falls MT
230 AM MDT Fri Jul 25 2025

.KEY MESSAGES...

 - Seasonal average temperatures are expected for this forecast
   period.

 - Today through Thursday there will be daily chances for showers
   and thunderstorms across North-central, Central, and
   Southwestern Montana.

 - Isolated thunderstorms on Saturday will produce strong to
   severe wind gusts.

&&

.DISCUSSION...

 - Meteorological Overview:

Today an upper-level ridge builds in over North-central, Central,
and Southwestern Montana. This will warm temperatures up a few
degrees to above seasonal averages. This combined with southwest
flow aloft will allow scattered showers and thunderstorms to form
across Central and Southwestern Montana Friday afternoon and
evening. Due to dry surface to mid-levels the main risk from any
thunderstorms today will be gusty winds and lightning.

Saturday through Thursday the upper-level ridge remains over the
area. This combined with stronger southwest flow aloft and periodic
upper-level shortwaves moving through the upper-level flow will
allow there to be scattered showers and thunderstorms across North-
central, Central, and Southwestern Montana each afternoon and
evening Saturday through Thursday. At least a few storms will be on
the stronger side Saturday through Thursday. Due to an increase in
monsoonal moisture with the southwest flow aloft there will be a
greater coverage of storms on Saturday than on Friday. Due to an
increase in upper-level moisture Tuesday through Thursday, isolated
thunderstorms will have the potential to produce flash-flooding. The
primarily concerns from any thunderstorm Saturday through Monday
will be strong winds and large hail. Saturday through Thursday
temperatures will fluctuate a few degrees but generally stay around
seasonal averages.

 - Forecast Confidence & Scenarios:

Today there is a 25 - 40% chance for thunderstorms south of the
Montana 200/US Highway 87 Corridor between Great Falls and
Lewistown. On Saturday the Storm Prediction Center (SPC) has issued
a Marginal Risk (5% chance for wind gusts in excess of 58 mph within
25 miles of a point) for all of North-central, Central and
Southwestern Montana south of a Teton to Choteau to Blaine County
line. On Sunday there is a 20 - 50% chance for thunderstorms across
North-central, Central, and Southwestern Montana. On Monday and
Tuesday there is a 30 - 55% chance for thunderstorms across North-
central, Central, and Southwestern Montana. -IG

&&

.AVIATION...
25/06Z TAF Period

VFR conditions with mainly clear skies and light surface winds
prevail through Friday morning. Breezy west to southwest surface
winds increase by mid-day Friday under an increasing west-
southwest flow aloft. Widely scattered shower and thunderstorm
development is expected across SW MT Friday afternoon with cells
tracking NE into central MT by Friday evening, affecting
locations as far north as KHLN and KLWT. Gusty/erratic winds and
lightning are the primary concern with convection late Friday with
some terrain obscuration also possible near cells. Hoenisch

Refer to weather.gov/zlc for more detailed regional aviation
weather and hazard information.

&&

.PRELIMINARY POINT TEMPS/POPS...
GTF  91  55  86  56 /   0   0  10  20
CTB  85  50  80  50 /   0   0  10  10
HLN  91  56  88  55 /  20  20  30  20
BZN  91  52  89  51 /  20  20  20  20
WYS  81  38  80  39 /  20   0  10  10
DLN  85  48  84  48 /  30  20  30  10
HVR  93  55  87  55 /   0   0  10  30
LWT  87  55  84  53 /  10  30  20  40

&&

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

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