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Area forecast discussion 
National Weather Service Pocatello Idaho
306 am MDT Wednesday Apr 1 2015

Short term...today through Friday. A larger area of low pressure
remains over eastern Idaho through tomorrow night...before high
pressure returns for a bit. The very strong winds overnight are
slowly dying down but will remain locally strong for the rest of
the day. Overall winds will be sustained at 15 to 30 miles per hour with
those higher gusts. Localized pockets of blowing dust are still
possible as well. We are letting the Wind Advisory expire at 3am
and are not looking to put one out for this afternoon and evening
based on less widespread impacts. That said...the day shift may
need to pull the trigger on another wind if winds and blowing dust
are a little more prevalent. Otherwise...the big story is the much
colder temperatures and showers. The highest concentration both
days will be in the afternoon and evening hours as we can tap into
what instability is out there. We may see a thunderstorm or
two...especially tomorrow but for now are leaving it out of the
written forecast. Showers today should be confined to north of a
Hailey-Soda Springs line with the best chance north of a Stanley-
Palisades line. For Thursday...showers are possible just about
anywhere but the highest percentages for seeing moisture fall will
be northeast of a Hailey-Preston line. Precipitation amounts will
be light...but it's certainly possible that a quick accumulation
of snow is possible causing temporary travel headaches. For the
valleys...we should see a mix of rain and snow as well as graupel.
Highs will struggle to get out of the 40s even for lower
valleys...with 20s and 30s for the mountains. Overnight lows will
be pretty cold as well. Under high pressure Friday...dry
conditions with a 5-10 degree warmup is on tap. Keyes

Long term...Friday night through Wednesday. Pattern remains
progressive through the extended but GFS and European model (ecmwf) have lost
consensus. Deep trough along Pacific coast Saturday ejects across
east Idaho through the weekend. Sunday appears to be the most active
day in the period. Have nudged probability of precipitation upward slightly as well as winds
with strong cold front shifting through the region. Both models hold
on to an amplified trough over the coastal states early next week.
The differences lie in how sharp the trough is and therefore how
much ridge occurs over the intermountain west and central rockies.
Further...by Tuesday...the European model (ecmwf) drags the base of the trough well
into the southwest US leading to more of a split flow across Idaho
headed into midweek while the GFS carries a more consolidated and
less amplified trough through the region. By the end of the period
both models shift trough into the plains states with ridge building
into the intermountain west. It is notable however that some
ensemble solutions continue to hold on to trough over the region.
Have generally blended solutions beyond Sunday. Cooler temperatures
expected for early to middle next week...closer to normal for this time
of year. Dmh

&&

Aviation...strong winds beginning to subside slightly over east
Idaho early this morning. All indications point to strong middle level
flow weakening by middle morning. As gradient continues to
relax...should be able to continue to hold off on any low level wind shear remarks
in snake plain terminals. East Idaho remains under the influence of
upper system however so light snow showers expected to continue
along The Divide. Some indication that weak precipitation could form along
edge of snake plain into the eastern Highlands very early this
morning. At best would earn a vcsh remark for both kida and kpih but
will hold off until better indications. Better chance for showers
this afternoon and evening mainly ksun/kida. Do not expect more than
MVFR ceilings under showers...with both kbyi/kpih remaining VFR
through tonight. Dmh

&&

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

$$

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