010
FXUS65 KTFX 282032
AFDTFX

Area Forecast Discussion
National Weather Service Great Falls MT
232 PM MDT Thu Aug 28 2025

.KEY MESSAGES...

 - This afternoon rain showers will continue across much of the
   area with Central and North-central Montana seeing rain showers
   tomorrow.

 - This afternoon and Friday it will be cool with temperatures
   warming up Saturday through Monday.

 - Friday and Saturday morning patchy fog will form in some areas.

&&

.DISCUSSION...

 - Meteorological Overview:

This afternoon there is weak upper-level flow over North-central,
Central, and Southwestern Montana. Due to a surface high, monsoonal
moisture is being pulled into Montana. Due to this combined with
vorticity maximums aloft there will be scattered showers across most
of North-central, Central, and Southwestern Montana this afternoon
through this evening. Due to surface heating this afternoon there
will be enough instability for isolated thunderstorms to form. Due
to the recent rain some locations in Southwestern Montana will see
patchy fog Friday morning. On Friday there will be weak upper-level
flow over North-central, Central, and Southwestern Montana. Due to a
surface high, monsoonal moisture is being pulled into Montana. Due
to this combined with vorticity maximums aloft there will be
scattered showers across most of North-central and Central Montana
on Friday. Due to surface heating on Friday, in the afternoon and
evening across North-central and Central Montana there will be
isolated thunderstorms.

On Saturday morning due to the recent rainfall any areas that have
clear skies will see patchy fog. On Saturday an upper-level ridge
will build back in over North-central, Central, and Southwestern
Montana. This will warm temperatures back up with dry weather. On
Sunday and Monday the upper-level ridge remains over North-
central, Central, and Southwestern Montana. This will allow
temperatures to warm up further with mostly dry weather. On
Tuesday a weak cold front will move through the area which will
cool temperatures down and bring precipitation chances to the
area. On Wednesday an upper-level ridge builds back in over the
area which will warm temperatures back up with mostly dry weather.

 - Forecast Confidence & Scenarios:

There is a 10% chance for fog across the valleys of Southwestern
Montana Friday morning. There is a 10 - 20% chance for fog across
North-central and Central Montana Saturday morning. There is a 20 -
50% chance for thunder on Friday across North-central, Central, and
Southwestern Montana. There is a 20 - 50% chance for a quarter inch
of rain or greater on Friday across North-central and Central
Montana. On Friday there is a 20 - 40% chance for a half inch of
rain east of a Havre to Great Falls line in North-central Montana.
Overall there is high confidence in the upper-level pattern for
this forecast period. However, on Tuesday some deterministic
models bring a weak cold front while others do not. As a result on
Tuesday there is high uncertainty in the forecast. -IG

&&

.AVIATION...
28/18Z TAF Period.

Monsoonal moisture, which was firmly in place over the Northern
Rockies, will bring scattered to numerous showers to most of
Southwest through North Central Montana over the next 24 hours.
Low-VFR/VFR conditions will predominately prevail, but scattered
to temporary MVFR conditions are possible at the KHLN, KBZN, KEKS,
and KWYS terminals through 03z Friday. Widespread mountain
obscuration will occur through the 2818/2918 TAF period. - Moldan

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

&&

.PRELIMINARY POINT TEMPS/POPS...
GTF  57  74  53  83 /  60  60  30  10
CTB  55  72  47  83 /  40  50  10  10
HLN  56  74  54  82 /  60  60  20  10
BZN  52  74  50  79 /  70  50  20  10
WYS  40  71  37  71 /  70  30  20  10
DLN  46  75  46  77 /  40  20  10  10
HVR  59  77  54  84 /  40  50  30  10
LWT  54  70  51  76 /  70  60  40  20

&&

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

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