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Area forecast discussion 
National Weather Service Pocatello Idaho
154 PM MST sun Feb 1 2015

Short term...the latest model runs have three disturbances
embedded in westerly flow off the Pacific that in quick succession
cross southeast Idaho. The first will come through tonight and
early Monday...the second Monday night and the third Tuesday
afternoon and overnight into Wednesday morning. Timing is quite
difficult given the speed of these disturbances. Total
precipitation as well is difficult. There could be some convective
feedback in the models given that there have been a few lightning
strikes today just off the coast...that could explain some widely
varying precipitation amounts in the models. It looks like the
second and third disturbances will bring more rain and snow than
the first. Therefore have issued a Winter Weather Advisory for
Monday evening through Wednesday morning for snow in the central
mountains and the eastern Highlands. The snow amounts and snow
levels have also been complicated by stretches of warm and cool
air embedded in the flow. Have blended the results together and
estimated the first disturbance tonight/Monday could bring 1 to 3
inches above 5500 feet elevation....little accumulation at lower
levels. Snow levels Tuesday should rise to near 600 feet. The
second an third disturbances could bring 5 to 10 inches of snow
above that level. The Bench areas east of Pocatello and Idaho
Falls may see an inch or so Monday night. Receiver station

Long term...Wednesday night through next Sun night. Fairly good agreement
on the Wednesday night wrap-up of the winter storm starting during the
near term period. Also...good agreement on a storm for Friday/Friday night
by both GFS and the European model (ecmwf). Sharp differences develop for the weekend
segment of this extended forecast. European model (ecmwf) is very dry while the GFS
brings in the next strong and moisture-laden shortwave on Sunday.
Have just broad-brushed the last 24 hours due to the uncertainty.
Main focus of the precipitation will be the west side of the central
Idaho mountains and corner where Idaho-Mt-WY all meet. Not much is
occurring in the south end of the forecast area. The other
remarkable thing is the warm air mass expected...high temperatures
will be near normals for middle- to late March...and low temperatures
very mild and more like late April. However...did not buy the
middle-50s forecasted by the latest edition of the GFS MOS--will have
to see if this continues and have left temperatures alone. Strong
wind aloft could be brought down to the surface...mainly with the
Friday/Friday night storm. Messick


Aviation...incoming front with precipitation should break up the
fog problem that the three plain airdromes have suffered for the
last several days. Only kida seems to be in a position to receive
some snow...with the other airports are either too far south where
precipitation will be limited to the mountains. In the case of ksun
the northwesterly flow kicks in late tonight and again most
precipitation there is limited to mountains above The Wood River
Valley. Thus expect kida to have the most problems with IFR mainly
due to ceilings. Low ceilings also expected at kpih. Messick


Pih watches/warnings/advisories...
Winter Weather Advisory from 5 PM Monday to 5 am MST Wednesday

Winter Weather Advisory from 5 PM Monday to 5 am MST Wednesday



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