482
FXUS65 KPIH 182352
AFDPIH

Area Forecast Discussion
National Weather Service Pocatello ID
452 PM MST Tue Nov 18 2025

.KEY MESSAGES...

- No high impact systems expected through the weekend but some
  isolated showers will be possible each day.

- Temperatures to remain at or slightly above climatological
  norms through next week

&&

.SHORT TERM /THROUGH WEDNESDAY NIGHT/...
Issued at 120 PM MST Tue Nov 18 2025

Afternoon satellite imagery shows continued mid/high level
clouds streaking across eastern Idaho today. Have seen a few
breaks from time to time across the Magic Valley and parts of
the Snake Plain allowing a bit more sunlight to shine down on
the area but for the most part, it`s been another mostly cloudy
day. Temps however remain on the warmer side of normal with low
to mid 50s being observed across the lower elevations with 40s
across the high country. Precip hasn`t been too much of an issue
today and it likely won`t be through daybreak tomorrow aside
from maybe a very isolated rain/snow shower around Island Park
or into the central mountains. Overnight lows should be
seasonably mild, once again, with lower elevations low running
within a few degrees, above and below, the freezing mark. As we
head towards daybreak Wednesday, a weak upper level impulse will
swing through the area and hi-res CAMs show the potential for
some light showers to develop mid-morning across the central
mountains and into the SE part of the area, perhaps even into
the Snake Plain. These would be light, isolated to scattered in
nature, and of relatively low impact however. Snow levels
generally remain above 7kft so rain is the most likely precip
type for MOST locations. Winds should remain light for Wednesday
along with continued above normal temps for mid November.
Expect upper 40s to lower 50s across much of the lower valleys
tomorrow, mid to upper 40s across the high country.

&&

.LONG TERM /THURSDAY THROUGH TUESDAY/...
Issued at 120 PM MST Tue Nov 18 2025

Plenty of active weather continues throughout the Western half
of the United States during the extended forecast period, but
we are hard pressed to get any or much of it to make its way
into Eastern Idaho. On Thursday, on area of low pressure will be
dropping into northern California and while that brings about a
15 to 20 percent chance for some showery activity in parts of
the Central Mountains and South Hills, that low will continue
its drop southward through California and take most of the
moisture with it. This low will open the door for some cooler
air to work its way into our area though, as we see highs go
from mostly low to mid 50s on Thursday to 40s on Friday. Weak
ridging keeps us looking mostly dry for Friday, Saturday, and
Sunday. Models are advertising the potential for a cold front to
pass through late Monday into Tuesday which would bring another
drop in temperatures and a small chance for precipitation, but
it doesn`t look very impressive at this point. We will keep
watching and waiting!

&&

.AVIATION /00Z TAFS THROUGH 00Z THURSDAY/...
Issued at 452 PM MST Tue Nov 18 2025

VFR conditions and insanely little wind (most guidance 4kts or less
except a touch higher at KSUN) are generally expected over the next
24 to 36 hours for aviation interests across southeast Idaho. Two
areas of low pressure, one to our north and one to our south, will
bring weak troughing and some isolated showery activity, but any
rain chances remain low enough to keep out of the TAFs everywhere
except KDIJ Wednesday afternoon (going with VCSH there). In this
overall pattern, two items do particularly catch our interest for
the forecast though. One, large areas of stagnant/persistent mid-
level clouds are currently blanketing portions of the region. These
clouds are not moving much, and are also not being well modeled in
the NBM or even the HRRR. Thus, our forecast stays pessimistic and
maintains these clouds throughout this evening into tonight. They
might trend more SCT at KPIH and KBYI with time, but confidence is a
bit low. Two, both the NBM and HRRR are developing impactful fog and
low stratus across the eastern Magic Valley including KBYI late
tonight into Wednesday morning. Current RH values are leaning dry at
less than 60%, and MOS guidance doesn`t agree with this scenario,
but on the other hand the HREF shows a near-saturated surface layer
tonight and winds are nearly non-existent, suggesting things will
remain quite stagnant. We`re still evaluating this potential and
watching trends in the guidance...experience also tells us that
either fog or low stratus would likely be favored if development
occurs, but probably not both. For now have hinted at this overall
potential in the 00z TAF with 6SM BR VCFG SCT005 from 09-17z/2-10am
Wednesday, but if it "goes", it`s going to go hard with IFR if
not LIFR conditions likely. Stay tuned for updates.

&&

.PIH WATCHES/WARNINGS/ADVISORIES...
None.

&&

$$

SHORT TERM...McKaughan
LONG TERM...AMM
AVIATION...01