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fxus65 kpih 211126 

Area forecast discussion
National Weather Service Pocatello Idaho
526 am MDT Sat Sep 21 2019

Update...added some patchy fog across portions of the snake plain
up into the Island Park area. Also included it for the Teton
valley, Swan Valley and Stanley Basin areas. Any impacts should be
more isolated in nature and not be around later this morning.


Previous discussion... /issued 219 am MDT Sat Sep 21 2019/

Short and Sunday. Lingering rain and snow showers
are on tap across mainly the mountains and Highlands. Northwest
will tend to favor areas near and east of I-15 through early
this evening, but other terrain areas should see a least a small
chance of a shower. We could see a few showers across the snake
plain, but the potential is fairly low. Do not expect anywhere
near what we saw in the past 24-48 hours across portions of central
and eastern Idaho. Speaking of all the rain and snow we've seen
since yesterday, we will be monitoring for valley fog
potential...but for now we aren't including anything in the
forecast. We wouldn't be surprised if something develops in a few
isolated spots. Snow levels will hover between 7000-8000ft this
morning, climbing to 8500-9000ft this afternoon. Heavier showers
will likely drive them 500-1000ft lower. A few storms are possible
around Island Park, but that is about it thunder wise today. It
will be warmer today, but still running below average for the end
of September. Tomorrow will be dry as high pressure drifts
overhead briefly. We will climb another 10 degrees from today,
putting right at average high temperatures. Keyes

Long term...Sunday night through next Saturday. The next storm
approaches central and eastern Idaho Sunday night and Monday.
While better consistency and confidence isn't there yet, it does
appear that split flow will leave US dry over most of eastern
Idaho. The best (and potentially only) chance of seeing
precipitation is across the central mountains south through the
Magic Valley and into the South Hills. The blend of models is
insisting we should see some chance of showers (even if it's
slight) for all of eastern Idaho, but that may be overdone
considering the trends. Where we have more clouds and that
better potential for showers, it should be a few degrees cooler
Monday...while farther east expect similar high temperatures to
Sunday. Dry and breezy northwest flow sets up until we reach the
end of next week. Ensembles and forecast trends still point toward
a colder, wet pattern returning to much of the northwestern
states. A strong ridge well upstream will drive an over
trough/area of low pressure into our neck of the Woods. Some
indications are that this will be a colder system than the one
exiting now. Keyes

Aviation...exiting low will continue to hamper Airport operations
during the morning hours this morning with both ceiling and visibility
impacts, but only the three eastern airdromes: kdij, kida, and kpih.
Kdij may be an all-day event, but it should be primarily carrying
enough fuel for an alternate. There could be some IFR conditions
there. Current taf for kida has some IFR for visibility in br, but not
sure about this, as precipitation was much better at krxe compared
to kida. There is, however, a good potential. Kpih should clear
during the morning with no problems after. Kbyi and ksun are out of
the influence of this low and should be ceiling and visibility unlimited by afternoon, with only
mid-level cigs to be concerned about. Wind should be light with
slightly higher afternoon gustiness. Messick

Fire weather...warming and drying will commence after a very wet
day for the eastern Idaho dispatch center area, while the western
zones continue to warm and dry. However, temperatures are continuing
cool enough where humidity is not a concern, unless it is too high
for prescription burning. Winds will be down compared to Friday
as well. Warming and drying trends will continue Sunday, but the
upper level ridge will start breaking down Sun night for the
central Idaho mountains. Rain and upper elevation snow threat will
develop Monday during the day, but even then it is not much. Snow
level starts out around 10000ft elevation and lowers only to the
9000ft elevation. Warming and drying return for Wednesday with
temperatures rising to slightly above normal for this time of
year, which would be mid-70s for the Snake River Plain. Next good
chance for precipitation is on Thursday with a low that comes out
of the Gulf of Alaska. Messick


Pih watches/warnings/advisories...

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