Scientific Forecaster Discussion

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Area forecast discussion 
National Weather Service Pocatello Idaho
248 am MDT sun Apr 20 2014

Short term...today through Wednesday. A dry cold front is making
its way through southeast Idaho this morning with winds in the
vicinity of the front gusting to 40 to 45 miles per hour. MOS guidance still
showing winds beginning to decline after 15z today as gradient
weakens. As the weather settles down later today...we begin to focus
on a major shift in the pattern over the west on Tuesday. A deep
upper trough will dig into the Pacific coast early Tuesday
morning and is expected to have a negative tilt. Models are
indicating this will be a wet and windy system impacting southeast
Idaho Tuesday and Wednesday. Isolated thunder is possible as well
given the orientation of the trough and the distribution of
instability. Hinsberger

Long term...Wednesday night through Sunday night. GFS and European model (ecmwf) in
agreement with the upper trough deepening to an upper low over
northern Montana by Wednesday evening. Mountain snow showers will be widespread on
Wednesday...while valley rain/snow showers will be tapering off from west to
east. By Wednesday evening...only widely scattered mountain snow showers will remain as
upper ridging builds in. The upper ridge moves off to the east by
Friday as a new upper trough moves into the Pacific northwest. The GFS and European model (ecmwf) are
in agreement again...but they soon part company. The European model (ecmwf) rotates a
short wave through Idaho by Sat morning and holds the main system offshore...
while the GFS brings the main system onto the West Coast. As far as
the resulting forecast...not much difference. Precipitation chances increase on
Friday...becoming fairly widespread on Sat. Snow levels are expected to
run above 7500 feet both Friday and Sat. The overall pattern remains
unsettled through sun...so will carry precipitation through sun and slowly back
off the chances Sun night with temperatures remaining cool through the
weekend. Hedges
&&

Aviation...a dry cold front passing through southeast Idaho early this morning
will result in gusty SW winds. Winds will slowly decrease this afternoon.
Ceiling/visible will remain VFR through tonight. Hedges
&&

Pih watches/warnings/advisories...none.
&&

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