149
FXUS65 KPIH 282358
AFDPIH

Area Forecast Discussion
National Weather Service Pocatello ID
458 PM MST Sun Dec 28 2025

.KEY MESSAGES...

- High pressure ridging will support dry conditions, only light
  winds, and a gradual warming trend today through much of the
  upcoming week.

&&

.SHORT TERM /THROUGH MONDAY NIGHT/...
Issued at 126 PM MST Sun Dec 28 2025

Satellite imagery shows ridge of high pressure along the PacNW
coast, with recent low pressure system continuing to depart across
the northern Great Plains and another deep Pacific trough well off
the coast. East Idaho in cool northwest flow which is expected to
continue through the short term period. Dry conditions, light winds,
and a gradual warming trend is expected. Temperatures tonight remain
cold, and would not be surprised to see some places result in lows
below current forecast, given the recent snow cover and continued
clear skies.

&&

.LONG TERM /TUESDAY THROUGH SUNDAY/...
Issued at 126 PM MST Sun Dec 28 2025

Tue through next Sun. The 500mb upper level ridge over the western
states easily reaches heights of 5700m, highly anomalous for this
time of year; to do that will require very warm air. There is an
eastward shift that puts the ridge axis overhead by Thu. By Fri(2
Jan) afternoon there is a risk of the ridge beginning to break down
with 65 percent of the solutions making up the clusters of model
runs that feature the break-down. For Sat, 45 percent of the
solutions have the upper level ridge sufficiently broken down
that precipitation is likely, with the remainder have the low
still to the west. So no major cold front is expected to sweep
through during the period.

Most of the solutions have southwest upper level flow developing
with the shifting of the ridge axis. The shift means the
temperatures are likely to return to being mild for the time of year
and the pattern is very much like an atmospheric river event for Fri
and the rest of the weekend. A less than 15 percent of the solutions
show more zonal flow.

&&

.AVIATION /00Z TAFS THROUGH 00Z TUESDAY/...
Issued at 457 PM MST Sun Dec 28 2025

VFR conditions forecast at all terminals with generally light and
variable winds. Some FEW to SCT high clouds will return tonight into
the first part of Monday, but skies will clear again Monday
afternoon. Models show around a 15% chance of CIGs below 1k at KPIH
and KIDA overnight/Monday morning, with only around a 10% chance
of CIGs below 500 feet at KIDA.

&&

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

&&

$$

SHORT TERM...DMH
LONG TERM...Messick
AVIATION...Cropp