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Area forecast discussion 
National Weather Service Pocatello Idaho
305 am MDT Thursday Sep 29 2016

Short through Sunday. Broad southwest flow through
the depth of the atmosphere will become firmly established across
the region today and will persist through the weekend, allowing a
continuation of warmer than average temperatures through much of
the weekend. Today, enhanced moisture combined with an area of
low pressure will move northeastward across the region, bringing
scattered showers along with isolated thunderstorms to southeast Idaho
today, most numerous during the afternoon and early evening. It
appears the southern and eastern Highlands along with the central
mountains will be the most favored locations to see this activity.
The strongest storms may produce gusty outflow winds and brief
heavy rain this afternoon into early evening. Moisture then
lingers across the region through Friday, with showers and
isolated thunderstorm potential lingering across these same areas,
although coverage will be somewhat less on Friday compared to what
is expected today. The next wave of low pressure embedded in the
southwest flow will arrive on Saturday, with latest indications
suggesting an organized precipitation band will develop as a
result. At this time it appears this band will set up across the
central mountains early Saturday morning and will track eastward
across southeast Idaho through the day while gradually weakening. This
may put a damper on outdoor activities Saturday. Additional
showers and isolated thunderstorms will be possible Sunday,
although this activity will likely be less organized than what is
expected Saturday.

Long term...Monday through next Thursday. Forecast guidance
continues to come into better agreement regarding the track and
strength of a closed low pressure system that is expected to track
across the northern Great Basin and into Wyoming Monday into
Tuesday. This track is favorable for widespread precipitation
across southern and eastern portions of southeast Idaho, and have trended
the forecast in this direction. The heaviest precipiation is
currently forecast to fall late Monday into Tuesday across the
southern and eastern Highlands, with precipitation trending
lighter and less organized moving northward away from the low. The
low will bring a significant cooldown to the region as well, with
temperatures falling 10 to 20 degrees from Sunday to Monday. Snow
may accumulate to elevations as low as 7,000 feet Monday night
into Tuesday across the southern and eastern Highlands, which
would potentially mean snowfall for passes such as emigration
pass, Georgetown Summit, Geneva Summit and Pine Creek Pass. There
is still some lingering differences with respect to the track and
strength of this system, so future changes in the forecast will
certainly be possible. Drier conditions along with gradual warming
appears to be the most likely outcome at this time as we progress
into midweek next week. Ad/receiver station


Aviation...convective activity moving into southeast Idaho this
morning will set the stage for scattered rain showers with isolated
thunderstorms this afternoon. Greatest impact will be at kida and
kpih with mfr ceilings possible with stronger showers or
thunderstorms between 19z-24z. Looks like a smaller window for ksun
from about 20-23z. On Friday...focus of showers looks to
be late afternoon and evening at ksun and kbyi. Receiver station


Fire weather...moist and unstable air is surging northward into southeast
Idaho this morning ahead of the low pressure disturbance moving into
the coast. Scattered showers with isolated thunderstorms are
expected from about noon until sunset today with most activity
angled across the south central and eastern Highlands. There will
be some showers in the central mountains. Estimate precipitation
from 0.03 to 0.11 inches with higher amounts from isolated
stronger storm cells. Activity diminishes this evening, then focus
on Friday will be a band of showers and isolated thunderstorms
oriented along a surface front with best precipitation from near
Ketchum to Leadore,around 0.10 to 0.15 inch. A pretty good band of
showers should form over the snake plain on Saturday. A temporary
period of dry air is anticipated Saturday night and at least part
of Sunday. Then the disturbance off the Pacific tracks across
northern Nevada and Utah with some showers wrapping back into
Idaho. May not be a lot of the storm system left by then, but snow
levels drop to near 7000 feet elevation in the central mountains,
sloping to about 8000 feet towards Bear Lake. Receiver station


Pih watches/warnings/advisories...


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