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Area forecast discussion 
National Weather Service Spokane Washington
903 am PDT Friday may 22 2015

Synopsis...
the Memorial Day weekend is expected to be warmer than average
with afternoon temperatures in the 70s and 80s. Look for scattered
showers and thunderstorms this weekend into next week. Some
thunderstorms will be capable of producing heavy downpours and
frequent lightning.

&&

Discussion...

Rest of today: the main changes have been to adjust the areal
coverage of pcpn and sky cover based on the radar loops, vsbl
satellite and sfc obs. The flash food watch for the east slopes of
the Cascades will remain en effect for recent burn
scars...including the Carlton complex...Mills Canyon...and the
Chiwaukum complex. However, given the easterly flow....the
strongest storms are anticipated along the crest of the Cascades.
Blended precipitable water shows anomalous moisture over the Cascades. Slow
steering flow will also help to produce localized, prolonged heavy
downpours. It still looks like the potential for thunder this
afternoon is on track for most of the rest of ern WA and the cntrl
Idaho Panhandle as well. The exception may be the north Idaho
Panhandle where the cap is a bit stronger. The high cape/weak deep
layer shear profiles support an enhanced heavy downpour threat for
most thunderstorms this afternoon and evening. Small hail is also
possible. The highest threat areas will be near the Cascades as
well as the Lewiston/Pullman region and the cntrl Idaho
Panhandle. Bz

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Aviation...
12z tafs: scattered high based showers will continue to drift
west from the vcnty of kmwh toward the keat area this morning,
with mainly light rain expected. Convection will again develop
late today, after 20z. Expect a similar trend as experienced on
Thursday with activity starting in the Blue Mountains and Camas
Prairie and than drifting west toward the Cascades. Today
anticipate more development in the Cascades under the easterly
low level flow and the approaching shortwave from the northwest.
The hrrr shows convection will begin to fire over the high terrain
of the Cascades and Blue Mountains after 20z Fri. Gusty outflow
winds and brief heavy rain will be the main threats from
thunderstorms, which should decrease after 03z. /Rfox.

&&

Preliminary point temps/pops...
Spokane 82 53 80 53 79 53 / 10 10 10 10 20 30
Coeur D'Alene 81 52 79 53 79 52 / 10 10 10 10 20 30
Pullman 78 49 73 47 75 49 / 20 10 10 10 10 10
Lewiston 81 56 79 54 82 56 / 30 20 20 20 20 20
Colville 86 53 83 55 82 52 / 10 10 10 10 30 30
Sandpoint 81 50 80 48 77 50 / 10 0 10 10 20 20
Kellogg 81 50 79 49 78 50 / 20 10 30 20 20 20
Moses Lake 84 56 84 55 83 54 / 40 10 10 10 20 20
Wenatchee 82 59 83 58 82 57 / 60 30 10 10 20 20
Omak 86 53 85 54 83 53 / 20 20 10 10 30 20

&&

Otx watches/warnings/advisories...
Idaho...none.
Washington...Flash Flood Watch from 1 PM this afternoon to 8 PM PDT this
evening for east slopes northern Cascades.

&&

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