781
FXUS65 KPIH 181102
AFDPIH

Area Forecast Discussion
National Weather Service Pocatello ID
402 AM MST Tue Nov 18 2025

.KEY MESSAGES...

- Showery weather continues throughout the week with low
  confidence in timing and amount for any location.

- Cooler temperatures but still above climatic normals for the
  time of year through the period.

&&

.SHORT TERM /THROUGH TONIGHT/...
Issued at 401 AM MST Tue Nov 18 2025

Satellite this morning shows a wide range of cloud heights and we
continue to monitor for any fog formation and associated impacts.
Two cutoff lows will shift further inland today, with one tracking
along the US-CA border and the other southeast along the CA coast.
While conditions will largely remain dry over Southeast Idaho,
South/Southwest flow aloft today will advect weak moisture from the
southern low and keep chances for high elevation showers in the
forecast through the first part of the day today. Heading further
into the afternoon and evening hours, models show moisture signals
remaining further north and south of us. We will begin to see clouds
scattering later today, allowing daytime highs to reach around 10
degrees above climatological norms, warming into the 50s across most
of our valleys and 30s and 40s in the mountains and mid-
elevations/mountain valleys, respectively. With less cloud cover
overhead tonight, overnight lows will run several degrees cooler
tonight with widespread 20s and 30s areawide.

&&

.LONG TERM /WEDNESDAY THROUGH MONDAY/...
Issued at 223 PM MST Mon Nov 17 2025

The extended portion of the forecast remains unsettled but also
fairly low-impact as the upper flow aloft looks to remain split
across our part of the country. Models show a couple of cutoff lows
moving into California from mid week and into the weekend while most
moisture stays clear of eastern Idaho. Still could see some isolated
high elevation showers at some point but models seem to be going
back and forth with this. Temperatures will remain on the
warmer side of normal by around 5 degrees. This equates to upper
40s and low 50s for highs in the valleys but there is still a
decent spread within the model guidance so things could still
fluctuate a bit over the days ahead. Either way, not seeing any
high impact systems between now and early next week.

&&

.AVIATION /06Z TAFS THROUGH 06Z WEDNESDAY/...
Issued at 1019 PM MST Mon Nov 17 2025

Gradually improving/lifting/thinning cigs are forecast for KPIH,
KIDA, and KBYI tonight and Tuesday, with winds remaining under 7kts.
There will be quite a bit of low-level moisture in place given
cooler temperatures and recent rain/showers...right now guidance is
not biting off on fog formation (with good agreement actually), but
will need to keep an eye especially on KIDA in case some combination
of fog and/or low stratus tries to develop for awhile overnight into
Tuesday morning. Confidence remains somewhat low at KSUN for the
first half of the forecast period...MOS guidance (which usually does
well with their wind direction) is still suggesting a possible
switch to the usual northwest nocturnal down-valley flow imminently,
and while the switch hasn`t occurred yet at the airport, vsbys and
cigs continue to improve regardless. Still seems likely VFR
conditions will rule the rest of the night, although watching T/Td
spreads as the surface remains near 100% saturation for now...
perhaps until the NW wind kicks in and nudges things drier. As far
as moisture goes, KDIJ is the winner, and we maintain borderline
MVFR cigs overnight and Tuesday morning there in the Teton Valley.
There are mixed signals in our various sources of guidance on fog
and low stratus potential, but suspect things will remain quite
saturated following long-duration rainfall today. Maintain 6SM BR
VCFG for now from 08-17z/1-10am Tuesday with SCT008, and we`ll need
to monitor trends for any needed amendments for greater impacts.
There is a 30% chance of IFR conditions due to cigs, vsbys, or
both.

&&

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

&&

$$

SHORT TERM...Cropp
LONG TERM...McKaughan
AVIATION...01