Area Forecast Discussion
Issued by NWS Pocatello, ID

Current Version | Previous Version | Graphics & Text | Print | Product List | Glossary Off
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36

FXUS65 KPIH 222105

Area Forecast Discussion
National Weather Service Pocatello ID
205 PM MST Wed Nov 22 2017

.SHORT TERM...Tonight through Saturday afternoon. Snow levels remain
elevated around 9000 feet of elevation through Thursday evening,
then lower to about 6000 feet on Friday with passage of a
disturbance and surface cold front. Snow accumulation in the
mountains limited to 1 to 2 inches with 3 inches possible on the
higher peaks. Patchy fog and low stratus can also be expected in the
Upper Snake Highlands, including Raynolds Pass.  This alone does not
pose travel difficulties, but winds of 15 to 25 mph are expected in
the Snake Plain both Thursday night and Friday. The strongest winds
will probably be Friday, and may reach 20 to 30 mph. Gusty cross
winds will develop on US 26 and 30, also SH 33. RS

.LONG TERM...Saturday night through next Wednesday. The latter half
of this weekend will see the upper ridge shifting to the east and a
return to a rather active period through Monday night, possibly
Tuesday. GFS continues to support a more progressive pattern than
the ECMWF. Thus, the timing of many things remains uncertain, the
biggest of which will be the changeover from rain to snow. GFS
solution would put a slow-down to the Monday morning commute, while
the ECMWF snow levels support rain until the Monday afternoon
commute. We are generally looking for about 7 to 10 inches of snow
in the Central Mountains for the duration of the storm Sunday night
through Monday night. Snow amounts seem to taper off shortly after
the snow levels drop to valley floors, but may still impede travel
in the passes. Light snow amounts are possible in the Snake Plain,
but some of the benches could see 1 to 2 inches. Strong winds
associated with the surface front will become apparent on Monday as
well with winds 25 to 30 mph across the Snake Plain and South
Central Highlands, giving a strong crosswind component along I-84
and I-15. Extended MOS guidance suggests even stronger winds,
approaching warning levels. Tuesday and Wednesday look cool, but
much drier. Hinsberger


.AVIATION...Mid and high clouds are streaming through the upper
ridge across the West today. Upstream observations indicate cloud
bases around 8500 to 11000 ft, though forecast BUFKIT soundings
indicate drying in the mid-levels, but support a cirrus layer
through tomorrow morning. Soundings also indicate surface layers
nearing saturation, which may promote fog development. NAM MOS
guidance shows greater fog potential for KIDA. KDIJ remains a
challenge with the ceiling lingering around 2000 ft. HRRR sounding
supports improvements there around 22Z, but NAM3km holds off until
around 04Z-05Z. Weighted forecast closer to HRRR. Hinsberger




$$ is the U.S. government's official web portal to all federal, state and local government web resources and services.