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Area forecast discussion 
National Weather Service Spokane Washington
519 PM PDT Monday Jul 28 2014

Synopsis...
hot temperatures and dry weather will continue through midweek.
Thunderstorms chances will increase during the latter portion of
the work week as monsoonal moisture overspreads the inland
northwest.

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Discussion...
tonight...quiet and mild weather expected tonight due to strong
upper level ridge persisting over the region. Skies will
generally be clear as weak upper level disturbance currently over
extreme southeast Washington shifts into western Montana. Light
winds will prevail while relative humidity recoveries will be
quite poor over the mid-slopes and ridges. Fx

Tuesday and wednesday: the ridge will be in full control over the
inland northwest midweek, with continued hot temperatures
expected. Tuesday looks to be the hottest day of the week, as 850
mb temperatures are around 27 degrees celsius. Little in the way
of cloud cover will get in the way, and not much breeze will be
present to make it feel a little "cooler." Expect whatever high
temperatures you experience to day (monday) to go up another
couple of degrees, but then fall a few degrees for Wednesday
afternoon. This is in response to an increase in cloud cover as
monsoonal moisture overspreads eastern portions of the region.
Temperatures will likely begin the day on Wednesday on the warm
side, as mid-level cloud cover increases beginning Tuesday night
(and continues into wednesday). A weak disturbance embedded in
the weak flow aloft may be enough to trigger some afternoon
showers and thunderstorms. Any precipitation would be more likely
over far eastern Washington into the Idaho Panhandle. This is not
a strong disturbance so widespread precipitation is not expected.
However, with the presence of thunderstorms, some new fire starts
are possible. But with increased moisture, hopefully any
thunderstorm would stay on the wet side. TY

Wednesday evening through Monday...longwave ridge with axis
placement to the east over central Montana remains in place due to
longwave trof/low remaining in place offshore and in the vicinity
of the Gulf of Alaska and a similar stagnant trof remaining over
northeast North America which essentially keeps the ridge from
moving anywhere. This persistent pattern allows for a persistent
hot forecast for temperatures and the potential for shortwave
disturbances of varying intensity to run up under or along the
west side of the ridge axis in a trajectory from the south or
southwest and possibly kick off thunderstorms through the
interval. As it stands now there is run to run model consistency
in passing such disturbances through the area in the form of a
negatively tilted trof rotating around the periphery of the Gulf
of Alaska low on Friday, otherwise there have been spottier
depictions in the models of smaller disturbances with limited
moisture/energy/lift coming up from the south. With this in mind
the pops and sky cover ramp up highest Friday and continue on into
through the remainder of the forecast with the idea the longwave
ridge axis should be further east once the Friday negatively
tilted trof passages which allows for a slightly better storm
track for disturbances to move up from the south/southwest.
One thing very interesting to note is discussion about the 12z
European model (ecmwf) bringing a closed wet circulation up from the south for the
weekend. If one rocks a 12z European model (ecmwf) 500mb height, vorticity, and
quantitative precipitation forecast loop back and forth it does seem to look like this feature is
built upon bits of old remant moisture and energy ejected out of
Tropical Storm Hernan which is out if the east Pacific off the
coast of Mexico right now. /Pelatti

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Aviation...
00z tafs: clear skies and light winds will prevail for the next 24
hours under high pressure. Rj

&&

Preliminary point temps/pops...
Spokane 68 99 68 95 67 95 / 0 0 0 10 10 10
Coeur D'Alene 62 97 64 92 62 93 / 0 0 0 10 20 10
Pullman 58 97 60 93 61 92 / 0 0 10 20 20 10
Lewiston 71 103 72 99 68 99 / 0 0 10 20 20 10
Colville 59 100 60 98 59 97 / 0 0 0 10 10 10
Sandpoint 55 94 57 92 57 92 / 0 0 0 10 20 10
Kellogg 62 93 62 89 60 90 / 0 0 0 20 20 10
Moses Lake 65 104 67 101 67 99 / 0 0 0 10 0 10
Wenatchee 72 102 71 100 70 100 / 0 0 0 0 10 10
Omak 67 102 66 101 66 100 / 0 0 0 0 0 10

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Otx watches/warnings/advisories...
Idaho...heat advisory until 8 PM PDT Tuesday for Lewiston area.

Washington...heat advisory until 8 PM PDT Tuesday for lower Garfield and
Asotin counties-Moses Lake area-upper Columbia Basin-
Washington Palouse.

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