382
FXUS65 KPIH 212040
AFDPIH

Area Forecast Discussion
National Weather Service Pocatello ID
240 PM MDT Fri Mar 21 2025

.SHORT TERM...Rest of Today through Saturday Night.
Satellite continues to show clouds streaming in from the west as our
next shortwave approaches. A few showers begin to move into our
western areas later this evening, but the bulk of the precipitation
arrives around midnight and continues on and off through the first
half of Saturday. In the valleys, temperatures will be in the 40s
for afternoon highs and low to mid 30s overnight, meaning a mix of
rain and snow with a slightly better chance for light snow during
the nighttime hours, but overall little to no snow accumulation is
expected in the eastern Magic Valley and Snake River Plain with the
latest HREF data showing about a 10 percent chance of an inch of
snow in this area. Snow totals will be higher through our mid and
upper elevation zones with about 2 to 4 inches in the mid elevations
and 4 to 8 inches in the higher elevations. Some of our mountain
passes like Galena, Pine Creek, and Emigration will be closer to the
6 to 10 inch range. With these snowfall totals and wind gusts
expected to be in the 40 to 50 mph range for many, Winter Weather
Advisories continue across parts of the Central Mountains and
Eastern Highlands. Up in the Island Park/Henry`s Lake area, we are
watching for some snow squall potential as the cold front moves
through and gusts pick up. It is low-confidence squall potential,
but a non-zero chance. Main impacts would be for portions of I-15
north of Dubois and US-20 north and east of Idaho Falls. This is an
area that is not currently covered by any winter or wind product,
but there is still the potential for periodic travel impacts in
these zones due to blowing snow. With sustained winds of 30 to 35
mph and gusts of 40 to 50 mph for many on Saturday, went ahead
and issued a Wind Advisory for a good portion of the eastern magic
Valley, Snake River Plain, parts of the South Hills, and out
across the Mud Lake area. By Saturday evening winds should be
backing off and most of the precipitation will be wrapped up with
cooler air in place for Saturday night and temperatures falling
into the teens and 20s for many. AMM


.LONG TERM...Sunday through Friday.
After the early weekend system, spring rebounds across East
Idaho. We may see some lingering showers mainly across the north
into Sunday, but the general trend will be for a ridge to build
into the Intermountain West, leading to strong warming trend into
mid week. By Tuesday/Wednesday, lower elevation temperatures show
a better than 70% probability of reaching over 70 degrees,
especially for Wednesday. Even more impressive is that overnight
lows for low elevations stay well into the 40s. This will have
longer term hydrologic snow melt impacts, and we will lean into
this by early next week. By late next week, the ridge weakens with
advancement of next robust Pacific trough. There are differences
in the ensemble clusters with respect to timing and depth of the
trough, but in general they all trend toward a cooler wetter
pattern to end the week. DMH


&&

.AVIATION...18Z Friday to 18Z Saturday.
VFR conditions in place at all East Idaho terminals with
locally breezy winds this afternoon. Next system working into PacNW
coast expected to begin impacting East Idaho this evening.
Precipitation already occurring across portions of Oregon/Washington
should arrive at KSUN and KBYI by mid evening, spreading across the
remainder of the terminals by late evening. Temperatures remain warm
enough to maintain -RA at KBYI/KPIH, -RASN at KIDA until FROPA early
Sat with MVFR CIGS. KSUN and KDIJ will likely be all -SN with MVFR
or lower CIGS. Precipitation drops off quickly behind the front, but
could be briefly intense in nature. Sustained winds during the day
could approach 35kts and gusts may exceed 50kts KBYI and KPIH 18z-
21Z Saturday. DMH


&&

.PIH WATCHES/WARNINGS/ADVISORIES...
Wind Advisory from 6 AM to 6 PM MDT Saturday for IDZ051>058.

Winter Weather Advisory from 6 PM this evening to midnight MDT
Saturday night for IDZ060-062>064-066.

Winter Weather Advisory from 6 PM this evening to noon MDT
Saturday for IDZ072-073.

&&

$$