Area Forecast Discussion
Issued by NWS Pocatello, ID

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FXUS65 KPIH 180856

Area Forecast Discussion
National Weather Service Pocatello ID
256 AM MDT SUN SEP 18 2016

.SHORT TERM...Today through Tuesday. Strong westerly flow
continues over the Pacific Northwest and Idaho today. This will
bring some moisture over our area today, keeping some light
showers going over portions of the central mountains and Upper
Snake Highlands. The pattern is also conducive for more afternoon
winds, although speeds look a little lighter than what we had in
the forecast. It stills like just enough for a Lake Wind Advisory
for this afternoon and evening. For tonight, the moisture surge
begins to diminish but expect lingering showers over the eastern
highlands and central mountains. We should be dry and warm on
Monday but that won`t last long. As the flow turns southwesterly
heading into Tuesday, some moisture sneaks across the central
mountains and along the Montana border for occasional showers
starting tomorrow evening. With the flow changing this direction,
temperatures will remain on the warm side of normal.

.LONG TERM...Wednesday through next Sunday. If there was one word
that would sum up a good chunk of the extended, if would be WET!
Greater confidence exists now in the models that starting midweek
on through Friday, we will see plenty of moisture falling here.
Now there is still some question on just how much will fall as
right now the models still are tracking the low through and across
the state for the end of the week. The GFS continues its more
southern route vs the ECMWF which is still showing a northern
route, albeit not as far north as prior runs.

While it`s WAY too early to get into specifics, it does appears
most of eastern Idaho could be in store for a good soaking over
that 2-3 day period. Snow levels may end up down in the
6500-7500ft range by Friday as well. Temperatures will drop into
the 50s for valley highs and 30s/40s in the high country for
Thursday and Friday. We should slowly dry out as we head into next
weekend with a slow warming trend.  Keyes


.AVIATION...VFR the general rule today. There will be some
shower activity north of a line from from KSUN to Palisades
Reservoir, with a slight chance of MVFR ceilings associated with
rain showers over the higher terrain east of KIDA. Snow levels near
12000 feet elevation today and Monday. Southwest winds 20-25 knots
with gusts to 30 knots this afternoon in the Snake Plain affecting


.FIRE WEATHER...Disturbance advancing across central and northern
Idaho today with widely scattered rain showers in the mountains
north of a line from Sun Valley to Henrys Lake. Winds will be the
main threat in the Snake Plain and Lemhi and Bitterroot Range,
however relative humidity will be mostly in the 25 to 35 percent
range this afternoon. Two to three degrees warmer, drier, and with
less winds on Monday across the forecast area. Upper level winds
begin to turn southwest late Monday night and Tuesday with the
development of a low pressure system near the Washington coast.
Isolated showers may develop in the central mountains over to Monida
Pass under this flow. Confidence is increasing for this system to
move towards northern Nevada Wednesday night and Thursday, placing
it in a favorable position to bring wetting rains to much of
Southeast Idaho. At this time, areas most favorable are from the
Boulder/Pioneer Mountains eastward. The Southern Sawtooth may see
upwards of 0.10 inch rain but that area may be on the fringe of
heavier precipitation. The Salmon NF, Zone 475 could see less than
wetting rains, but Zone 476 could be better positioned. It should be
Friday night or early Saturday before this disturbance clears the
Caribou-Targhee Forest. Snow levels Thursday on the back or west
side should drop to 8000 to 9000 feet elevation. RS


.PIH Watches/Warnings/Advisories...
Lake Wind Advisory from noon today to 8 PM MDT this evening for


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