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fxus65 kpih 152028 cca 

Area forecast discussion...corrected
National Weather Service Pocatello Idaho
128 PM MST Fri Nov 15 2019

Short term...tonight through Sunday night. A rather fast moving
storm crosses eastern Idaho this evening and Saturday. We will see
winds picking up this evening and remain gusty overnight and
tomorrow across the snake plain/Magic Valley and ridgetops.
Precipitation will be light overnight and Saturday. We are looking
for under an inch of snow across portions of the central
mountains, Centennial/Island park and eastern Highlands south to
near Palisades. We could see snow briefly down to valley floors in
these areas, but any real snowfall would be at/above 7000ft. These
amounts should not impact travel on higher passes. However, there
is a very low confidence issue that could become an impact
quickly albeit briefly. Some of the higher resolution models and
soundings indicate some patchy freezing drizzle is possible across
the upper snake plain and Teton valley overnight and tomorrow
morning. Again, there is very low confidence of it happening...but
feel it needs to be mentioned verbally. The actual chance is so
low, it isn't reflected in the official forecast at this time. Definitely
keep an eye out if you are travelling during these times though.
Otherwise, temperatures will be a few degrees cooler (especially
saturday) but still above average. Keyes

Long term...Monday through Friday. Upper ridge axis shifts across
east Idaho during the day Monday. Operational models and ensembles
still favor Pacific trough pushing inland and reaching Idaho during
the day Tuesday. Precipitation spreads across the region generally
on Tuesday and into Tuesday night. There is still quite a bit of
deviation with respect to the evolution of the trough but consensus
still supports a split albeit later than previous runs. This holds
trough together longer as it encroaches into east Idaho so if this
solution pans out there should be better chances of precipitation
across the region especially prior to the development of the split
Tuesday night. Base of split sinks to a closed low over the
southwest US by late Wednesday. This track would favor continued
light precipitation over the southern zones as the northern stream
trough passes by Wednesday, possibly lingering into Wednesday night.
By Thursday, features shift far enough east to allow amplified upper
ridge to tip over into the region. Thus expecting drier pattern for
the rest of the extended range. It should also be noted that the
ensembles indicate a lot of uncertainty in temperature spreads
through the extended, but trend should be toward cooling a little
bit each day after system drives through on Tuesday. Dmh


Aviation...trend continues with increasing cloud cover through the
region into tonight as a weak low pressure system slides across
Idaho. VFR conditions will continue through the evening, then will
see a shift toward MVFR overnight especially for kida/kpih. Kdij
will have the best potential of precipitation onset by late evening,
continuing overnight with potential for IFR around sunrise. There is
also a very low chance at seeing the potential for very light and
rather patchy areas of freezing drizzle particularly in the upper
snake plain, but there is not enough confidence in this yet to
mention it any forecast at this time. Winds on the increase
overnight as well, with widespread sustained winds around 15kts,
expected to continue to mid morning Saturday. Dmh


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