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Area forecast discussion 
National Weather Service Spokane Washington
1036 PM PDT Wednesday Jul 30 2014

Synopsis...
it will be partly cloudy and hot with isolated thunderstorms
through the end of the week and into the weekend. No significant
relief from the hot weather is forecast through the seven-day
forecast period. However, only a few spots may reach the 100-degree
mark. Isolated thunderstorms the next several days are not
expected to be strong or severe but could bring localized heavy
downpours.



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Discussion...tonight through Saturday night. The forecast area
will be located on the backside of an upper level ridge through
Saturday and will be influenced by a weak SW flow aloft. A few
disturbances in the flow may increase moisture and lift to a
presently unstable air mass...resulting in isolated thunderstorms.
Due to a weak mid-level shear and marginal instability...most
storms will be garden variety and diurnally driven. The main
concern will be the slow storm movement bringing heavy downpours.
Today there have been a few showers sitting near the northeast
mountains with storm movement less than 10 mph. Forecasters will
need to keep a close eye on storms that may develop near burn
scars in steep terrain. Thunderstorms will mainly be confined to
central and northern Idaho, but a slight chance of showers and
thunderstorms was added to all zones on Saturday. All models hint
at a shortwave off the coast edging inland that will steepen lapse
rates across eastern Washington on Saturday. Increasing clouds
will keep temperatures from climbing significantly during the
afternoon thurs-Sat, but the heat advisory for the Lewiston area
will be extended through Thursday evening as this area will have
overnight lows around 70 and afternoon temperatures in the 100-105
degree range.

Sunday through Wednesday...no major changes are expected in the
weather pattern during the remainder of the period. The Pacific northwest
will be influenced by a broad upper level ridge and an inverted
surface thermal trough. Afternoon temperatures will remain in the
mid 80s to mid 90s. A slight chance of thunderstorms is forecast
for the afternoon and evening on Sunday and Monday...as weak
impulses pass through the region. Of course, any threat of
thunderstorms brings fire weather concerns but there does not
appear to be any organized waves to increase shear and enhance
lift for significant lightning strikes. Moisture is limited as
well. Monsoonal moisture advection will primarily be directed
east of The Rockies. I've kept thunderstorms out of the forecast
for most of the area Tuesday and Wednesday as the flow is more
westerly. Models are in general agreement so confidence in the
continued hot temperatures is high...but there is uncertainty in
the thunderstorm forecast...particularly where thunderstorms will
be located Sunday and Monday. Wister

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Aviation...
06z tafs: VFR conditions expected the next 24 hours. Cu will
develop over the mtns in the aftn with cirrus moving in from the
south through the late afternoon and evening hours. Isolated
thunderstorm development is possible from the blue mtns to Lookout
Pass thurs afternoon/evening.

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Preliminary point temps/pops...
Spokane 67 96 66 93 65 92 / 0 0 0 10 10 20
Coeur D'Alene 62 94 59 92 62 90 / 0 0 10 10 20 20
Pullman 56 95 61 91 57 91 / 0 10 10 20 20 20
Lewiston 70 102 69 97 68 97 / 0 10 10 30 30 20
Colville 57 101 57 95 59 95 / 0 0 10 10 10 20
Sandpoint 54 92 52 89 56 87 / 0 0 10 10 20 20
Kellogg 61 93 57 90 62 87 / 0 10 10 20 20 30
Moses Lake 64 100 65 97 64 97 / 0 0 10 10 10 20
Wenatchee 71 100 67 96 71 97 / 0 0 10 10 10 20
Omak 65 100 63 98 68 97 / 0 0 0 10 10 20

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Otx watches/warnings/advisories...
Idaho...heat advisory from 1 PM to 8 PM PDT Thursday for Lewiston area.

Washington...heat advisory from 1 PM to 8 PM PDT Thursday for lower
Garfield and Asotin counties.

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