Area Forecast Discussion
Issued by NWS Pocatello, ID

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FXUS65 KPIH 221157
AFDPIH

Area Forecast Discussion
National Weather Service Pocatello ID
457 AM MST Sun Jan 22 2017

.SHORT TERM...Today through Tuesday. A moist cold front moves
into our Western areas late this morning and exits our Eastern
areas by Monday. Currently models are showing 2 to 5 inches of
valley snow with the exception of areas along the I-86 corridor
where a Trace to 2 inches is expected. Look for 6 to 12 inches of
mountain snow for the Central mountains, the Upper Snake
Highlands, the Caribou Highlands, the Wasatch mountains, and the
Eastern Southern Highlands. The Caribou Highlands and the Wasatch
mountains above 7500 feet could see 16 to 20 inches of snow. A
Winter Storm Warning is in effect for the Caribou Highlands and
the Wasatch mountains/Bear Lake Region. Winter Weather advisories
are in effect for all other areas except the lower snake river
plain. Today into Monday morning downslope Southerly winds will
keep temperatures elevated, particularly along the I-86 corridor
from Pocatello to Burley. Also, expect wind gusts of 25 to 40 mph
across the area today into this evening bringing blowing and
drifting snow. The higher wind gusts will be across the Southern
Highlands and Central mountains which will likely impact roads
particularly for mountain passes.

There is high uncertainty from Monday afternoon into Tuesday.
Both models develop a low. However, the Nam 12 model drops the low
south of our area and brings very little precipitation across our
area Monday afternoon into Tuesday. The GFS model develops the
low over our area and brings additional snow for the lower
Central/Pahsimeroi mountains and Upper Snake Highlands. With
cooler temperatures the GFS model is showing snow for the I-86
Corridor as well as additional snow for the Southern Highlands,
Caribou highlands and the Bear Lake region. Wyatt

.LONG TERM...Wednesday through next Sunday. Both the GFS and ECMWF
maintain a Canadian trough over the region while Pac moisture
undercuts a ridge developing off the NW coast helping to sustain
ongoing light snow shower activity across the region through at
least Friday morning. The ridge amplifies across the NW states
Friday afternoon and remains the dominant feature through Sunday
promoting dry conditions and colder nights. Huston

&&

.AVIATION...The next Pac low was advancing toward the NW coast early
this morning. Numerical models show the leading edge of the
associated precipitation plume advancing into SE Idaho around noon
today impacting all terminals through the afternoon hours and then
shifting into the SE highlands with some clearing across the CNTRL
Idaho mountains overnight. We will favor MVFR/IFR CIGS with the
initial onset of moisture at most terminals this afternoon (KBYI may
be the one exception) and then allow some improvement at KSUN
overnight as the focus shifts into the SE highlands. The models show
a fairly good clip of wind 20-35kt developing at and above the top
of the surface inversion this morning and continuing into the
afternoon. Wind already blowing out of the south at KPIH and KIDA so
the LLWS previously forecast at these terminals may be too
aggressive. Huston

&&

.PIH WATCHES/WARNINGS/ADVISORIES...
Winter Weather Advisory from noon today to noon MST Monday for
IDZ017-018-020-031-032.

Winter Storm Warning from 6 PM this evening to 6 PM MST Monday
for IDZ023-025.

Winter Weather Advisory from 6 PM this evening to noon MST
Monday for IDZ022-024.

Winter Weather Advisory from 6 PM this evening to 6 PM MST
Monday for IDZ019.

&&

$$



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