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Area forecast discussion 
National Weather Service Spokane Washington
428 am PDT Monday Aug 31 2015

Synopsis...
a cool, occasionally breezy and showery weather pattern is
expected through the week with the inland northwest laying close
to the polar storm track.

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Discussion...

Today through Tuesday...longwave trof lingers over the area
through this forecast interval and beyond which allows for
shortwaves running through it to maintain their forcing and
moisture feeds thus pops through most of this interval run quite
high along the Cascade crest and near the Canadian border
depicting such activity. The 0-6km above ground level average winds from the
models i've looked at this morning suggest convection should move
to the northeast at 30 to 35 mph through this time period which is
fast enough to keep from having a high rainfall rate cell sit in
one place for too long so for locations east of the Cascade crest
I still see minimal signs for anything beyond very isolated and
localized debris flow problems on burn scars if they occur at all.
Given the trof solution with some convection and associated cloud
cover forecast daytime high temperatures should run on the cool
side of normal while overnight lows will stay closer to normal but
may lie slightly on the cool side as well. This pattern continues
to favor winds blowing out from the southwest but with slightly
less intensity as they did yesterday (sunday). Of additional note
is a mention of patchy valley and lowland fog in some locations
due to sundays abundant rainfall in some spots, this is in
addition to the persistent mention of smoke from area fires.
/Pelatti

Wednesday through Thursday...model agreement is good and
consistent over multiple runs in depicting an unsettled and
continued troffy pattern over the region. High confidence exists
for a cooler than normal...showery and breezy regime over the
forecast area. Wednesday will feature another cold front passage
with elevated breezy to windy conditions with gust potential in
the 30 mph range over much of the exposed terrain of the area.
Not as bad as last Saturday but none-the-less probably the
breeziest day of the extended period. Showers with this front may
bring another tenth or two of an inch of rain to many locations
with a small chance of thunderstorms across the northern
mountains.

Friday through Sunday...models consensus diverges somewhat
with the latest ec dropping a strong cold closed low right into
the forecast area with a possible stratiform rain bearing
deformation region wrapping around it...which would argue for a
significant amount of much needed rain for much of the area. The
GFS also shows a trough passage but less wet and aggressive
suggesting a decent chance of showers on Friday but a general
drying trend Saturday and Sunday. So forecast confidence is
reasonably high for another cool and unsettled day Friday with the
potential for garden variety thunderstorms over much of the region
but confidence deteriorates sharply for the later periods of the
forecast. /Fugazzi

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Aviation...
12z tafs: smoke from regional fires will impact klws and kpuw tafs the
most from time to time given the prevailing southwest flow.
Additionally some morning fog and stratus will form in valleys to
the north and near the Spokane and Coeur D'Alene area
tafs. Southwest flow is likely to become gusty again in the
afternoon and evening hours...otherwise VFR conditions should
prevail. /Pelatti

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Preliminary point temps/pops...
Spokane 72 51 75 54 68 47 / 20 20 10 10 10 10
Coeur D'Alene 71 50 74 52 67 44 / 20 20 10 10 20 10
Pullman 73 48 76 51 68 44 / 10 10 10 20 30 10
Lewiston 81 55 83 58 74 52 / 10 10 10 10 20 10
Colville 68 49 73 50 69 44 / 30 30 20 20 30 30
Sandpoint 69 46 72 50 66 42 / 30 20 20 20 30 20
Kellogg 70 46 73 50 65 42 / 20 10 10 30 40 20
Moses Lake 77 53 77 53 72 47 / 10 10 10 10 10 10
Wenatchee 74 54 74 54 71 51 / 20 10 10 10 10 10
Omak 72 48 74 48 71 46 / 30 20 10 10 20 10

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Otx watches/warnings/advisories...
Idaho...none.
Washington...none.
&&

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