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Area forecast discussion 
National Weather Service Spokane Washington
438 PM PDT sun Aug 30 2015

Synopsis...
showers, thunderstorms and breezy winds will diminish through the
evening hours as a vigorous upper level weather system exits the
region. A cool, occasionally breezy and showery weather pattern is
expected much of next week.

&&

Discussion...

Tonight: isolated to scattered showers will continue into the
early evening as the upper level trough of low pressure crosses
the region. Much of this shower activity will be located across
the eastern half of the forecast area. Isolated thunderstorms will
also be possible through the early evening. I don't think we will
be able to generate enough instability for thunderstorms to be a
big threat. Strongest storms are expected to be across the
northern mountains with small hail, heavy downpours and gusty
winds to 40 mph possible.

Monday through tuesday: another shortwave trough will swing by the
region on Monday and Monday night. This system will mostly be a
glancing blow across the northern zones. The best dynamics will
remain well up into British Columbia. A weak warm front will swing through on
Monday. This will increase mid and high level cloud cover. The
cold front will then swing in Monday night. Neither front shows
much lift and only some light showers will be possible. Best
chances for precip will be across the northern mtns. Temperatures
will see a slight warming trend, but will still remain near to or
slightly below normal. /Svh

Tuesday night through Sunday. A broad upper-level trough will
remain anchored over the Pacific northwest during this time-
frame. Confidence is near to above normal that cooler temperatures
will be here to stay with afternoon highs in the 60s to 70s.
Overnight lows will largely be in the 40s to 50s with pockets of
30s in the northern valleys and on the highest peaks.
Precipitation chances will be centered around the timing and track
of embedded shortwaves pivoting within the mean trough. Models
suggest the first of these waves swings through the region Tuesday
night into Wednesday. Precipitation amounts do not look terribly
impressive but at this point, anything will help. There is lower
confidence regarding the track and time of the next slug of energy
so will trend pops toward climatology which mainly mentions a
chance of showers in the mountains. With the cooler trough aloft,
afternoon instability may be sufficient in generating light
showers each afternoon. As for thunder, the main threat looks to
be in the higher terrain near the international border Wednesday
afternoon and early evening. As for winds...breezy conditions are
possible each afternoon but the main periods we will emphasis
given the wildfires in the region will be Wednesday and Friday. A
cold front on Wednesday will bring a moderate push of winds with a
majority of the basin looking at sustained winds from 15 to 25 and
gusts toward 35 mph. Similar winds could be experienced on ridge
tops. These winds will be from the southwest. On Friday, a cold
front drops in from the north bringing a northerly push of winds
through the region. The narrow and north-S oriented valleys of
Okanogan Valley and Purcell Trench will receive the brunt of this
wind but northerly winds can be anticipated region-wide. Speeds
have been increased between 10-15 mph with this forecast package
and may need to come up further. Stay tuned. /Sb

&&

Aviation...
00z tafs: scattered showers and isolated thunderstorms will
affect extreme northeast Washington and the northern Panhandle of Idaho
behind a cold front moving into western Montana. Breezy west to
southwest winds will diminish after 03z. Low level moisture from
recent rainfall and light upslope flow may allow MVFR ceilings in
low stratus to form between around 10z to 16z...affecting
kgeg/ksff/kcoe. Kpuw could also see MVFR conditions but
confidence is low. /Ek

&&

Preliminary point temps/pops...
Spokane 50 72 53 75 54 68 / 20 20 20 10 10 30
Coeur D'Alene 48 71 51 74 52 67 / 30 20 20 10 20 40
Pullman 48 73 48 76 51 68 / 20 10 10 10 20 30
Lewiston 53 81 56 83 58 74 / 10 10 10 10 10 30
Colville 48 68 49 73 50 69 / 20 30 30 20 30 40
Sandpoint 47 69 48 72 50 66 / 30 30 20 20 30 50
Kellogg 45 70 47 73 50 65 / 40 20 10 10 40 50
Moses Lake 52 77 54 77 53 72 / 10 10 10 10 10 10
Wenatchee 53 74 54 74 54 71 / 10 20 10 10 10 10
Omak 50 72 50 74 48 71 / 10 30 20 10 20 20

&&

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

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