351
FXUS65 KPIH 252352
AFDPIH

Area Forecast Discussion
National Weather Service Pocatello ID
552 PM MDT Sat Apr 25 2026

.KEY MESSAGES...

- Cold temperatures at night will again challenge the freezing
  mark tonight and Sunday night. A combination of Frost Advisory
  and Freeze Warning is in place tonight for the Snake Plain.

- Weak low pressure over the northern Rockies and the Great
  Basin continue to threaten very light precipitation

- Slow warming will get temperatures near normal on Tuesday.

&&

.DISCUSSION...
Issued at 116 PM MDT Sat Apr 25 2026

Complex upper low remains in place over south central Canada
today. Strong shortwave rotating south around the low across the
PacNW is expected to pick up moisture extending northeast out
of low off California coast. That moisture arrives after
midnight tonight across the southern and southeast highlands,
spreading north through most of East Idaho (mainly east of a
line from Sun Valley to Challis) during the morning as the next
northern shortwave feature arrives. Overnight temperatures
remain cold, with a mix of FROST ADVISORY and FREEZE WARNING
through the Snake Plain. Any precipitation that falls early
enough will be snow even to valley floors, though accumulations
will be limited to areas generally above 5000 ft elevation.
Precipitation retreats to higher elevation areas only by mid-
day, but continues into Tuesday especially across the north as
the trough stalls across Western Montana. Total accumulations
across the Bear River Range and the Divide are generally 3-6"
through Monday night where uplift is maximized. Other higher
elevation areas look to be much less, in the 1-2" range.
Temperatures remain cold Monday night, and another mix of FROST
ADVISORY and FREEZE WARNING is anticipated.

For Tuesday and beyond, deterministic models are tending to push
the deep Canadian low east, slowly. The Northern Rockies and
East Idaho remain under the influence of shallow trough
connected to the Canadian low, and loosely connected to the
closed low off the California coast. These features slowly shift
east by late in the week ahead of pair of lows coming off the
Pacific by early weekend. Ensemble clusters pick up the pattern
in general, but continue with differences in the details. Thus
there should be a transition from unsettled to briefly drier
conditions Thursday and Friday, with showers returning by the
weekend. That said, isolated showers and a thunderstorm or two
may be possible each day over some portion of the region.
Temperatures trend warmer, but may remain cold enough to support
cold-related headlines at times through the Snake Plain for most
of the week.

&&

.AVIATION /00Z TAFS THROUGH 00Z MONDAY/...
Issued at 543 PM MDT Sat Apr 25 2026

Not expecting significant impacts through Sunday afternoon.
Will have widespread VFR conditions through the period with only
some scattered to broken mid and high level cloud cover. Will
see some moisture moving northeast from an upper-level trof over
Utah Sunday morning and did put vicinity showers for DIJ for
the afternoon tomorrow. Still think most precipitation stays
south of all TAF sites but DIJ could see some vicinity showers.
Look for overall light winds this evening through tomorrow
morning before expecting slightly breezy winds tomorrow
afternoon with gusts up to around 20 kts.

&&

.PIH WATCHES/WARNINGS/ADVISORIES...
Frost Advisory from midnight tonight to 10 AM MDT Sunday for
IDZ051-055.
Freeze Warning from midnight tonight to 10 AM MDT Sunday for
IDZ052>054.

&&

$$

DISCUSSION...DMH
AVIATION...TW