339
FXUS65 KMSO 020758
AFDMSO

Area Forecast Discussion
National Weather Service Missoula MT
158 AM MDT Wed Jul 2 2025

.DISCUSSION...

KEY MESSAGES:

- Potentially severe thunderstorms today mainly across west
  central Montana, southwest Montana, and Lemhi County, Idaho.

- A trough Friday and Saturday will bring thunderstorms and
  potentially heavy rain to portions of southwest and west central
  Montana.

- Long range ensembles are showing potential for an extended hot,
  dry period through mid July.

Another round of thunderstorms today will start in Lemhi County,
Idaho and move northeast. Some storms may be severe, with
convection allowing models showing potential wind gusts over 60
mph. Current model runs show the best potential for strong winds
in the southern Bitterroot Valley. With a trough approaching the
region, there will be more shear today than yesterday. This means
there is potential for more hail, and larger hail. It`s
interesting to note that even though dynamic models are showing
the potential for severe storms, machine learning models keep the
area of severe storms farther east. So overall, it`s marginal for
severe impacts with a 5% or less chance of being directly affected
by severe weather.

A trough moving out of the southwest Friday and this weekend will
bring another round of thunderstorms. This time though it will
bring some moisture from the southwest monsoon, and heavy rain is
possible with any storms. Ensembles have been consistent with
keeping the heavy rain Lemhi County, Idaho, the southern
Bitterroot valley, the Sapphire mountains and areas eastward to
the Continental Divide. Heavy rain on recent burn scars is a major
concern and this system is well aligned with the Daly fire from
last year which would directly impact Skalkaho Summit near the
falls.

In the longer term, ensembles have showing the potential for a
hot, dry ridge lasting from about July 9th through the 15th.
However, it`s notable that while AI ensembles show a similar
pattern, they aren`t as intense with the ridge or the heat. Any
way you look at it, the preponderance of models point to an
extended dry period of a week or more coming up.

&&

.AVIATION...An approaching trough will kick off another round of
thunderstorms again today. Terminals KSMN, KHRF, and KBTM are the
most likely to be affected with potentially severe storms. The
HREF is also showing the convection continuing into the night over
terminal KMSO, though severe storms are not expected there. While
terminal KGPI will miss out on most of the convection today, some
HREF members are showing a marginally severe storm moving through
there over night. Overall, it`s going to be a busy afternoon with
thunderstorms and it may continue into the evening or overnight
hours at KMSO and KGPI.

&&

.MSO WATCHES/WARNINGS/ADVISORIES...
MT...None.
ID...None.
&&

$$