004
FXUS65 KTFX 082053
AFDTFX

Area Forecast Discussion
National Weather Service Great Falls MT
253 PM MDT Tue Jul 8 2025

.KEY MESSAGES...

 - Heat returns today and Wednesday, along with a few gusty
   showers and thunderstorms each afternoon.
 - Cold front pushes through Thursday, bringing a few showers
   along with much cooler temperatures.
 - Cooler and drier through the weekend, with another cold front
   pushing through early next week.

&&

.DISCUSSION...

Upper level ridging currently entrenched over the Western US has
brought a warm air mass into North Central and Southwestern
Montana, with many lower elevation locations reaching into the 90s
this afternoon. While skies have been clear so far today, we have
noticed a few puffy cumulus clouds start to develop across the
higher terrain of Southwestern Montana. A few of these may
eventually grow into some virga showers or even dry thunderstorms
this afternoon, potentially producing lightning strikes and gusty
winds.

Wednesday will be another warm day across North Central and
Southwestern Montana, with highs once again reaching the 90s for
most lower elevation locations. With this said, the ridge will
begin to break down during the afternoon, which will result in
gusty winds and increased shower and thunderstorm activity across
the area, mostly across the Plains. A few of the showers and
thunderstorms could produce some strong, gusty winds due to the
very dry air near the surface, and overall synoptic winds and low
RH values could lead to increased fire growth and spread. Please
see the Fire section below for more information.

Beyond tomorrow, a cooler air mass will push into the area,
bringing another chance for some showers on Thursday but then
drier air follows for the weekend. Temperatures will rise a bit
over the weekend, but another cold front will push through the
area on Monday, keeping the mercury from getting quite as high
next week.

 - Forecast Confidence & Scenarios:

Overall forecast confidence remains high through the next few
days, with shower and thunderstorm activity on Wednesday being the
biggest impactful question mark. Most mesoscale models show at
least some shower and thunderstorm development during the
afternoon, though there remains some uncertainty to the coverage
and organization of the storms. Regardless of the organization of
the storms, even a weak shower will be capable of producing gusty
outflows due to the dry air mass in place. Ludwig

&&

.AVIATION...
08/18Z TAF Period

VFR conditions will prevail during this TAF period. The primary
concern for this TAF period is erratic, gusty winds from isolated
thunderstorms in Southwestern Montana. The only location that there
was high enough confidence to add a prob30 group for thunderstorms
with gusty winds was at the KBZN terminal. But there is a 10 - 15%
chance for showers and thunderstorms producing gusty winds at the
KEKS, KWYS, and KLWT terminal between 08/20Z and 09/03Z. Another
concern for this TAF period is gusty winds at KCTB terminal during
the beginning of this TAF period. The thunderstorms have the
potential to cause brief periods of mountain obscuration in
Southwestern Montana. Due to hot temperatures today and tomorrow
there will be density altitude concerns this afternoon and evening
and Wednesday afternoon with the hottest temperatures expected at
the KGTF and KHVR terminals. -IG

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

&&

.FIRE WEATHER...

Hot, dry, and windy conditions are expected on Wednesday as an
upper level ridge breaks down across the area. While later in the
year this would necessitate a Red Flag Warning, current fuel
moisture and ERC values remain relatively low across the area,
which will help reduce the overall fire danger tomorrow.
Additionally, a few gusty showers and thunderstorms will be
possible tomorrow afternoon, which could cause any fires that do
get started to exhibit erratic fire behavior around any showers or
thunderstorms. Ludwig

&&

.PRELIMINARY POINT TEMPS/POPS...
GTF  61  96  58  78 /   0  20  20  30
CTB  58  88  53  65 /   0   0  20  60
HLN  60  95  58  82 /  10  20  20  20
BZN  55  96  52  84 /  20  20  20  10
WYS  48  83  50  77 /  20  20  20  20
DLN  52  90  49  81 /  20  20  20  10
HVR  61  98  57  77 /  10  20  20  30
LWT  59  92  54  76 /  20  20  20  30

&&

.TFX WATCHES/WARNINGS/ADVISORIES...
Heat Advisory until 8 PM MDT Wednesday for Cascade County below
5000ft-Hill County-Northern Blaine County-Western and Central
Chouteau County.

&&

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