404
FXUS65 KTFX 282328
AFDTFX

Area Forecast Discussion
National Weather Service Great Falls MT
528 PM MDT Mon Sep 28 2026

Aviation Section Updated.

.KEY MESSAGES...

 - There will be isolated showers and thunderstorms in
   Southwestern Montana this afternoon and evening.

 - It will be windy on Tuesday across North-central Montana.

 - Today through Friday it will warm up to around seasonal
   averages with mostly dry weather.

&&

.DISCUSSION...
/Issued 216 PM MDT Mon Sep 28 2026/

 - Meteorological Overview:

This afternoon a weak upper-level trough moves over North-central,
Central, and Southwestern Montana. This will bring showers and
thunderstorms to Southwestern Montana this afternoon and evening. It
will warm up across the area with mostly dry weather north of I-90
this afternoon. On Tuesday there will be zonal (west to east) flow
over North-central, Central, and Southwestern Montana. This will
allow warm temperatures to remain with dry weather. On Tuesday there
will be strong low-level and mid-level winds. This will bring windy
conditions to North-central Montana with the strongest winds along
the Rocky Mountain Front. On Tuesday there will be light rain and
snow showers over the northern Rocky Mountain Front.

On Wednesday and Thursday zonal flow remains over North-central,
Central, and Southwestern Montana with strong low-level and mid-
level winds. This will bring warm and mostly dry weather to the area
with breezy conditons across North-central Montana on Wednesday
and Thursday. On Friday an upper-level ridge builds briefly in
over North-central, Central, and Southwestern Montana. This will
allow temperatures to warm up with mostly dry weather across the
area. Friday afternoon/evening an upper-level trough will briefly
move over North-central, Central, and Southwestern Montana. On
Saturday and Sunday an upper-level ridge will build back in over
North-central, Central, and Southwestern Montana. After a cool
day on Saturday due to the upper-level trough Friday evening
temperatures will rebound on Sunday. It will be mostly dry this
weekend. -IG

 - Forecast Confidence & Scenarios:

This afternoon there is a 20 - 35% chance for thunderstorms across
southern Gallatin and Madison Counties. This afternoon there is a
40 - 70% chance for a tenth of an inch of rain or greater in the
West Yellowstone area. On Tuesday across the Northern Rocky
Mountain Front there is a 60 - 80% chance for wind gusts of 75 mph
or greater. On Tuesday across the plains west of I-15 there is a
40 - 70% chance for wind gusts of 55 mph or greater. As a result a
High Wind Warning was issued for the northern Rocky Mountain
Front and plains west of I-15 from 12 AM Tuesday to noon on
Tuesday. -IG


&&

.AVIATION...
29/00Z TAF Period.

An area of showers and embedded thunderstorms situated along the
MT/ID/WY borders will continue to impact the KWYS area through
around 29/03Z. Then there will be low stratus and patchy dense fog
development in this area between 29/06 and 29/16Z. Other areas
will generally see VFR conditions, but increasing westerly flow
aloft will bring breezy to windy conditions. Winds initially
increase along the Rocky Mountain Front by 29/06Z due to mountain
wave activity. Wind gusts look to exceed 50 kts at times. This
will expand onto the plains by the morning hours, with the
strongest winds exceeding 40 kts at times near KCTB. - RCG

&&

.PRELIMINARY POINT TEMPS/POPS...
GTF  47  73  52  67 /   0  10   0  10
CTB  44  66  43  58 /   0  20   0  20
HLN  41  74  47  71 /   0  10   0   0
BZN  38  72  42  70 /   0   0   0   0
WYS  27  65  28  67 /  30   0   0   0
DLN  37  72  40  71 /   0   0   0   0
HVR  43  75  46  65 /   0  10  10  10
LWT  43  75  47  66 /   0  10   0   0

&&

.TFX WATCHES/WARNINGS/ADVISORIES...
High Wind Warning from midnight tonight to noon MDT Tuesday for
East Glacier Park Region-Eastern Glacier, Western Toole, and
Central Pondera-Northern High Plains.

&&

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