FXUS65 KMSO 080705
AFDMSO

Area Forecast Discussion
National Weather Service Missoula MT
105 AM MDT Sun Sep 8 2024

.DISCUSSION...A weather disturbance moving north and east out of
central Oregon will spread light rain showers and cause an
increase in winds across central Idaho and into west central and
southwest Montana this afternoon and evening. Given how dry the
atmosphere is currently, and how little available moisture there
is in the atmosphere with this system, we expect showers to mostly
evaporate before reaching the ground. In turn, this will generate
gusty winds, with periodic gusts as high as 30-35 mph possible
through this evening. For locations generally north of I-90, today
will be another hot and mostly benign weather day, though some
showers may make their way northward. Again, precipitation amounts
will be quite light, though winds may increase in areas of
showers if they make it that far northward.

Smoke and haze will be prominent today, and likely remain so
through Tuesday as the region undergoes a transition to a more
active, wetter, and cooler pattern by mid-week. Forecast
confidence is increasing that much of central Idaho and western
Montana could receive much-needed, beneficial rainfall amounts
with the mid-week low pressure system. In fact, for 48 hour
precip totals from Wednesday through Friday, there is now a 60%
probability of at least 0.50" of rain to occur across portions of
western Montana, and a 40% probability of at least 0.25" falling
across central Idaho. If we want to be really optimistic, the 90%
percentile (ie: 1 in 10 chance) for western Montana could total in
the 1.25 to almost 2.00 inch range. The caveat currently is the
timing and location of the heaviest bands of precip, thus the
uncertainty and the wide swings in potential amounts. All of this
to say: confidence is very high (90%) that our region will be
wetter and much cooler mid-week into next weekend. Temperatures
during the day both Thursday and Friday still look like they will
range in the upper 50s to upper 60s.


&&

.AVIATION...High pressure will result in mostly clear skies and
light and variable winds for KGPI today, while terminals further
to the south will see an influence from increasing shower activity
this afternoon and evening. Gusty winds associated with showers
could cause gusts of 30 knots at times for KMSO, KSMN, KHRF, and
KBTM after 08/1800Z through 09/0500Z until showers pass. Very
little precipitation will be actualized from showers, resulting in
mostly virga and blustery outflow winds.


&&

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

$$