550
FXUS65 KPIH 051830
AFDPIH

Area Forecast Discussion
National Weather Service Pocatello ID
1130 AM MST Fri Dec 5 2025

.KEY MESSAGES...

- Winter Storm Warnings and Advisories continue today and
  tonight.

- Windy to very windy conditions develop in the Snake River
  plain and eastern Magic Valley tonight and Saturday.

- Lighter rain and snow accumulations continue Saturday through
  at least Thursday.

- Very windy again Tuesday through Thursday.

&&

.SHORT TERM /THROUGH SUNDAY NIGHT/...
Issued at 206 AM MST Fri Dec 5 2025

Surface low continues to move through the northwesterly upper
level flow with plenty of moisture to work with. Precipitation
should be its heaviest today and tonight. With the passage of
the surface low to the east, precipitation accumulation rates
drop precipitously. The lowest threat period will be Sat night,
when things take something of a break at that point. Have not
changed anything in the current Winter Storm Warning product.

Temperatures will warm compared to yesterday, but not as quickly
as previous thinking, with temperatures staying below 40 deg F
for much of the area. Warming continues Sat for the highs, then
the clearing skies Sat night produce the coldest overnight lows
for the next six days. The cold start will bring some slight
cooling for Sun, then incoming cloudiness warms the overnight
lows some.

Wind starting late tonight in the eastern Magic Valley and the
lower Snake River plain has some potential to be very windy, and
continue that way through Saturday and into Saturday night. This
is due to the exit of the low to the east and should be a
westerly wind. A Wind Advisory is a distinct possibility but
will let another shift get a look as this time as it is just
short.

&&

.LONG TERM /MONDAY THROUGH THURSDAY/...
Issued at 206 AM MST Fri Dec 5 2025

The upper level ridge at the west coast continues to dominate
this pattern through at least Mon, the point at which cluster
analyzes were not available. This ridge has amplified, putting
higher 500mb heights over the forecast area which implies much
warmer temperatures; this is brought out in the MOS guidance
which indicates temperature exceeding 50 deg F by Tue in the
lower elevations, despite clouds and precipitation at 40 percent
chance or greater, depending on elevation. The other remarkable
aspect of this period is strong wind forecast nearly non-stop
until Thu afternoon. The European MOS indicates lower wind
strengths, but still significant. The European suite also has
lower chances for precipitation, and cooler temperatures, which
may be more correct based on current performance of the product
suites.

&&

.AVIATION /18Z TAFS THROUGH 18Z SATURDAY/...
Issued at 1125 AM MST Fri Dec 5 2025

Troublesome TAF period once again with another surge of moisture
expected to push through the area later this afternoon and
evening. Currently, widespread MVFR/IFR conditions are in
place at KPIH, KIDA and KBYI and will likely remain in place
into the midday tomorrow. Precip, mostly rain, will overspread
the area later this evening and into the overnight. A brief
period of -SN or -RASN will be possible at the initial onset of
precip in these locations before transition to all rain.
Mountain terminals, KSUN and KDIJ, will also see MVFR/IFR
conditions shortly with the latter likely to remain socked in
through much of the period. KSUN should start to see some
improvement by mid-morning Saturday. Winds will become breezy at
KPIH, KIDA and KBYI later this afternoon and continue through
the period.

&&

.PIH WATCHES/WARNINGS/ADVISORIES...
Winter Weather Advisory until 5 AM MST Saturday for IDZ053-072-
073.
Winter Storm Warning until 5 AM MST Saturday for IDZ058>066.

&&

$$

SHORT TERM...Messick
LONG TERM...Messick
AVIATION...McKaughan