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Area forecast discussion 
National Weather Service Pocatello Idaho
1020 PM MDT Tuesday Mar 31 2015

Update...the pressure gradient has started to increase across the
eastern Magic Valley bringing strong winds particularly for
Burley extending southeast along I-84 into Utah. Models are
indicating strong winds to move eastward this evening before
tapering off around 3 am. Have continued the Wind Advisory until 3
am. Winds will pick back up late tomorrow morning into tomorrow
afternoon but currently looks to be below Wind Advisory.

&&

Previous discussion... /issued 209 PM MDT Tuesday Mar 31 2015/

Short term...tonight through Friday.
Cold front has pushed through eastern Idaho with winds picking up
substantially early this afternoon. Wind advisories remain in
effect tonight with winds expected to continue after sunset and
through Wednesday. Expect to see some blowing dust on roadways
near plowed fields. May need another Wind Advisory on Wednesday as
well. Precipitation should be limited to the central mountains and
upper snake Highlands overnight with little snow accumulation
expected. Will have much colder conditions Wednesday and Thursday
behind the cold front with high temperatures actually below normal
for a change. Snow showers will be possible both days mainly in
the mountains with showers Thursday likely more widespread. Will
see some light accumulations at high elevations the next two days
but should generally be under 4 inches. Upper ridge pushes in
Friday and expect widespread dry conditions with some warming
expected.
Gk

Long term...Friday night through Tuesday...progressive pattern
expected through the extended as the ridge that had been a common
feature over the western Continental U.S. Over the past several weeks breaks
down. GFS...ECMWF...and their ensembles in reasonable agreement through
the period...with GFS hanging onto the closed low a bit longer than
the European model (ecmwf) early in the period which opens the closed low into a
long wave trough sooner. Used a general GFS/European model (ecmwf) blend with a slight
nod toward the GFS through the extended. Now for the details...
Friday night through Sunday...region will reside beneath
southwesterly flow aloft ahead of a closed low/trough that will move
ashore early Sunday. What this means in terms of sensible weather is
temperatures will moderate back to above seasonal norms by 5 to 10
degrees on Saturday and Sunday. Moisture will increase Sunday ahead
of aforementioned trough...promoting rain and snow shower development
beginning in the central mountains Sunday morning with the upper
snake Highlands and eastern Highlands getting into the act by
afternoon. Well mixed boundary layer later Sunday into Monday will
tap into stronger winds aloft as the jet core rounds the base of the
trough...producing gusty winds especially in the Snake River Plain.
Upper trough will slowly slide eastward Monday into
Tuesday...promoting showers these days...particularly in the
afternoon and evening as cold air aloft combined with early April
insolation steepens lapse rates. Overall precipitation amounts
through the period should be relatively light as precipitable water
values remain generally at or below climatology for early April...with
highest quantitative precipitation forecast of a couple of tenths of an inch...across favored
southwest facing slopes with much less precipitation in valleys. Main
changes were to increase probability of precipitation and sky cover slightly Monday and Tuesday
across the southern and eastern Highlands. Temperatures under this
regime will be up to 10 degrees below climatology early next week. Upper
heights will build over the region by midweek in response to a
deepening trough digging across the eastern Pacific...allowing for a
temperature rebound beginning by midweek.
Ad

Aviation...a strong cold front has passed through the region this
afternoon with gusty southwest-west winds up to 30-35 kts developing
at byi..Ida..and pih. Look for lighter southwest gusts up to 20 kts
at ksun by 00z. Some slight reductions in visibility may also be
experienced at pih and Ida with bldu. Winds should decrease some
this evening into the 10-20 knots range. A secondary boundary moves
through around 06z increasing winds into the 15-25kt range once
again..with these persisting through the taf period at
byi...Ida...and pih. Mainly VFR conditions expected through the
period...however ceilings may approach MVFR towards 06z and continuing
through the morning with vcsh...with the exception of byi.
Ad

&&

Pih watches/warnings/advisories...
Wind Advisory until 3 am MDT Wednesday idz017-021-022.

Wind Advisory until 3 am MDT Wednesday idz019-020-032.

&&

$$

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