850
FXUS65 KTFX 270604
AFDTFX

Area Forecast Discussion
National Weather Service Great Falls MT
1204 AM MDT Mon Jul 27 2026

.KEY MESSAGES...

- Hot temperatures continue through the work week, with the hottest
  temperatures expected late week into the weekend.

- Isolated to widely scattered thunderstorms remain possible each
  day this week, with the best chances occurring midweek focused
  primarily on terrain.

-Wildfire smoke will continue to impact the region through Tuesday
 with degraded air quality and areas of reduced visibility.


&&

.DISCUSSION...

 - Meteorological Overview:

Broad upper-level ridging will remain the dominant feature through
much of the upcoming work week, maintaining hot temperatures across
North Central and Southwest Montana. Persistent southwesterly flow
on the western periphery of the ridge will also continue to assist
in the transporting of wildfire smoke from the Pacific Northwest
into the region through at least Tuesday, resulting in degraded air
quality and reduced visibility especially across the Plains and
Northern Rockies. Afternoon highs will gradually warm through the
period, with the hottest conditions expected the late week. Weak
disturbances embedded within the southwesterly flow will
periodically move across the Northern Rockies. Aided by monsoonal
moisture streaming northward, weak shortwaves moving through the
southwesterly flow will support isolated evening convection each
day. Tuesday and Wednesday will feature slightly increased chances
as a pair of more pronounced disturbances move through the region.
Convection will remain primarily terrain focused, with the highest
probabilities across Southwestern Montana. Forecast soundings
continue to depict inverted-V profiles, supporting gusty and erratic
outflow winds as the primary hazard with any stronger thunderstorm.
Friday into Saturday, the upper-level ridge axis briefly extends
northward across the Rockies, supporting another round of warming
and pushing temperatures back up towards the 100 degree mark across
much of the plains and valleys.

Looking towards the latter half of the weekend into early next week,
ensembles guidance continues to suggest a transition towards a less
amplified pattern as toughing moves into Northwestern CONUS. As
toughing progresses eastward, the ridge begins to weaken and is
suppressed southward, supporting a modest cooling trend and breezier
conditions across the region. However, ensemble guidance continues
to indicate limited moisture accompanying the weakening trough and
subsequent toughing, resulting in low confidence for any meaningful
increase in precipitation.

-JR

 - Forecast Confidence & Scenarios:

Continued Hot Temperatures...

Wildfire smoke remains the primary forecast challenge through at
least Tuesday. High resolution modeling continues to depict elevated
smoke concentrations across much of the region with the greatest
impacts to air quality expect across the Northern Rockies and
Plains. Confidence is high that wildfire smoke will continue to
impact the region, though confidence in the placement and density of
the thickest smoke remains lower. As a result, continued adjustments
to forecast highs may be needed should smoke trends differ from
current guidance.

Confidence is high that Friday into Saturday will bring the hottest
temperatures of the forecast period as upper-level ridging briefly
amplifies over the Northern Rockies. NBM Probabilities indicate a 30
to 50 percent chance of reaching 100 degrees across much of the
plains Friday before increasing to 60 to over 90 percent by
Saturday. Valley locations are less likely to reach that century
mark Friday, though probabilities increase into the 40 to 50 percent
range by Saturday. The primary source of uncertainty remains the
extent and persistence of wildfire smoke, as thicker smoke could
limit daytime heating and result in muted afternoon highs.

Weakening Ridge, Cooling, and Moisture

Confidence decreases towards the end of next weekend as ensemble
guidance begins to diverge on the evolution of the upper-level
pattern. While most ensemble members favor a transition towards a
less amplified pattern, uncertainty remains regarding the timing of
the change and any associated increase in precipitation.

-JR

&&

.AVIATION...
27/06Z TAF Period

Regional wildfire smoke will continue to impact both slantwise and
surface visibility across most terminals of Southwest through
North Central Montana over the next 24 hours, most notably at the
KCTB, KHVR, KGTF, KLWT, and KHLN terminals where MVFR/low-VFR
conditions are expected. In addition to the smoke, isolated to
widely scattered shower will lift northeast from Idaho and near
the KWYS terminal through the morning hours on Monday, with the
main impact being mountain obscuration from CIGS of 9kft.

For KGTF: Light winds throughout the morning hours on Monday will
back to the southeast and east during the afternoon, with winds
backing to the northeast between 00-06z Tuesday. There a 10%
chance that wind speeds and/or gusts could exceed crosswind
components thresholds between 21-00z as winds are backing from the
southeast to the northeast. Smoke throughout the next 24 hours
will reduce visibility both at the surface and slantwise upon
ascent/descent. - Moldan

&&

.PRELIMINARY POINT TEMPS/POPS...
GTF  90  59  92  60 /   0   0   0   0
CTB  86  54  89  56 /   0   0   0   0
HLN  91  60  92  60 /   0   0   0   0
BZN  91  57  93  58 /  10  10   0   0
WYS  84  48  86  49 /  20  20   0   0
DLN  88  55  90  55 /   0  10   0   0
HVR  93  59  96  60 /   0   0   0   0
LWT  87  58  89  58 /   0  10  10  10

&&

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

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