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Area forecast discussion 
National Weather Service Pocatello Idaho
301 am MST sun Jan 25 2015

Short through Wednesday. Another morning of patchy
morning fog/low stratus as we remain under high pressure and under
the influence of an inversion over the valleys. Forecast soundings
suggest we may see freezing drizzle yet again this morning. Patchy
freezing fog is likely with webcams at Ririe and Sheep Falls
occasionally seeing reduced visibility. Morning fog will remain a
concern as long as the upper ridge remains over the area. Models
signal a change in the pattern on Tuesday as they bring a warm
system out of the Desert Southwest. This will help boost snow
levels to around 9000 to 10000 feet on Monday night. As
precipitation starts falling Tuesday...those snow levels will drop
back down to around 6000 to 7000 feet by Wednesday morning.

Long term...Wednesday through Saturday. For the most part...models
have been remarkably consistent with timing of the Baja California low crossing
Idaho Tuesday/Wednesday...exiting east middle day Thursday. Most of the
uncertainty lies with the speed of disturbances in the northern
branch flow through British Columbia and Montana. Total 48 hour
precipitation amounts vary with each run...but are staying in a
range close to 2 to 5 inches of snow in the eastern Highlands and
perhaps 1 to 3 in the central mountains. Snow levels around 7000
feet Tuesday...falling to 5000-5500 feet Wednesday. Models have
shifted towards a stronger high pressure ridge Thursday night
through Saturday in favor of a drier period than previous model
runs. Again we are watching those little waves in the northern
stream that bring changes with each model run. Receiver station

Aviation...widespread MVFR ceilings in the snake plain again this
morning. Winds at the surface are rather light and
variable...offering little clues to changes in the stratus. Winds at
the top of the stratus favoring a weak south-southwest
direction...keeping status pinned in the upper plain. Think we are
in for another day of overcast that does not improve beyond 3000
feet above ground level. Ksun eluded the status Saturday afternoon and should today
as well. Tonight and early Monday...surface pressure gradient leans
towards northeast or down valley direction and offers more
ventilation. Stratus will prevail at kida...kpih and kbyi early
Monday morning...then stratus thins and sun comes out perhaps by
26/17z. Receiver station

Pih watches/warnings/advisories...none.


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