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Area forecast discussion 
National Weather Service Spokane Washington
450 PM PDT Wednesday Jul 23 2014

Synopsis...
a strong storm system and associated cold front will move through
the region and tonight, bringing severe thunderstorms producing
large hail, strong wind, frequent lightning with pockets of heavy
rain. Cool and windy weather is expected for Thursday with less
chances of thunderstorms. Temperatures will rebound by the
weekend and be accompanied by dry conditions. Hot weather will
return to the area on Sunday and early next week.

&&

Discussion...
rest of the afternoon and tonight...

..severe thunderstorms continue be a threat through this
evening over much of the region...

Severe thunderstorms were moving through east slopes of the
Cascades through much of the day with flash flooding near some of
the recent burn areas such as the Carlton complex and Mill Canyon
fires. Flash flood warnings had been issued in this region since
early afternoon. Along with the heavy rain there had also been
reports of hail as large as a quarter.

Radar and satellite continue to show the progression of the cold
front and strong thunderstorms progressing through the Cascades,
Okanogan region and southern Washington as of 2 PM. These storms
will continue to progress swiftly north and east through this
evening with a potentially damaging and deadly combination of
frequent lightning, possible Golf Ball sized hail, strong wind
gusts to 60 miles per hour and very heavy rain causing localized flash
flooding.

Overall estimates of storms reaching the major metropolitan areas of
Spokane and Coeur D'Alene as early as 3 PM and progressing into
the northeast mountains of Washington and Idaho Panhandle shortly
thereafter. It is highly urged to take shelter this afternoon and
evening in a sturdy build until the the threat of these
thunderstorms pass. The overall threat of widespread severe
thunderstorms should pass by late evening but thunderstorms will
persist overnight near the Canadian border until around midnight.

Behind the cold front and thunderstorms, wind will continue to be
strong with 35 miles per hour gusts lasting into the late evening hours.

Please continue to check frequently on the evolution of this
dangerous situation from local radio and television news sources
and the National Weather Service Spokane web site at http://weather.Gov/Spokane.

Thursday through Saturday...
showers will still linger over the mountains especially north and
east in the Idaho Panhandle. Temperatures will be cooler Thursday
will a cool night Thursday night. Going into Friday and Saturday
Mountain showers will be greatly diminished and a warming trend
will begin as high pressure builds into the region. Tc

Sunday through wednesday: the heat returns to the inland
northwest. High pressure builds over the area for an extended
period of hot weather. But there are some flies in the ointment.
Both the European model (ecmwf) and GFS show a little ripple in the flow coming up
from the southwest sometime Sunday or Monday. This brings moisture
into the area which could bring a threat of high-based (i.E.
Mostly dry) thunderstorms. The best chance would be over southeast
Washington and the southern Panhandle for Monday. After that wave,
convection should mainly be confined to the south of our area, but
that could change with the next forecasts.

The other affect of this moisture is that it will play havoc with
the temperatures for Monday. Clouds overnight could result in rather
balmy low temperatures. Clouds during the day could shave a few
degrees off the high temperatures. At this point I cooled
temperatures a bit for Monday afternoon. Rj

&&

Aviation...
00z tafs: cold front will continue to move through the area into
through 06z bringing severe thunderstorms with wind gusts to 60
mph, large hail and heavy rain leading to temporary reductions
of ceilings to near MVFR. Cold air following the cold front will
continue gusty winds to 35 miles per hour with reduction in storm activity from
southern Washington to northern Washington and north Idaho after 03z.
Expect lingering showers and possibly an isolated thunderstorm over
the northern mountains for Thursday but all taf sites will
essentially be experiencing a drying period and breezy winds gusting
to 30 miles per hour into 00z Friday. Tc




&&

Preliminary point temps/pops...
Spokane 51 71 50 76 54 84 / 70 20 10 0 0 0
Coeur D'Alene 53 67 49 75 48 82 / 70 30 10 0 0 0
Pullman 49 69 45 75 44 83 / 60 10 0 0 0 0
Lewiston 57 78 54 83 55 91 / 40 10 0 0 0 0
Colville 53 71 50 79 48 87 / 80 30 10 0 0 0
Sandpoint 54 66 48 73 47 81 / 80 40 10 0 0 0
Kellogg 52 65 49 73 49 81 / 80 30 10 0 0 0
Moses Lake 56 75 53 83 53 89 / 60 10 0 0 0 0
Wenatchee 57 73 56 82 60 87 / 60 20 0 0 0 0
Omak 54 74 52 82 53 88 / 80 20 10 0 0 0

&&

Otx watches/warnings/advisories...
Idaho...Severe Thunderstorm Watch until 10 PM for north Idaho
Washington...Severe Thunderstorm Watch until 10 PM for East Central
Washington northeast and southeast Washington.
Flash Flood Watch until 11 PM PDT this evening for east slopes
northern Cascades- Okanogan Valley-Wenatchee area.





&&

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