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fxus66 kotx 261132 
afdotx

Area forecast discussion
National Weather Service Spokane Washington
432 am PDT Wed Jul 26 2017

Synopsis...
expect warm and dry weather for the next several days.
There is a slight chance of thunderstorms across southeast
Washington into the southern Panhandle late today into Thursday
afternoon. Breezy winds will also develop across the Columbia
Basin Thursday afternoon. Hot weather will return for the weekend
and into early next week.

&&

Discussion...
today through thursday: expect very warm and dry weather for much
of the region with a Flat Ridge of high pressure overhead.
Temperatures will warm 2 to 4 degrees over yesterday, making it
the warmest day of the work week. Winds will start off light and
increase out of the south by afternoon. Early morning cirrus blow-
off will thin out through the day. Watching the upper level
shortwave off the California coast, which is forecast to weaken
and lift northeast this evening, getting absorbed by the flow
aloft. This feature has been responsible for the convection over
Oregon the last few days. As this feature ejects, it's expected to
push deeper moisture over southeast Washington and the southern
Idaho Panhandle starting late this afternoon and through the night.
Instability will be on the rise this afternoon, although a weak
cap spans the region. There is a slight chance for thunderstorms
from the Blue Mountains and the Camas Prairie late today. As the
wave and mid level moisture lift northeast overnight, there is the
small potential for nocturnal activity to persist through the
night and have extended it to clip parts of the lc valley,
southern Palouse and into the central Panhandle.

By Thursday, pressure gradients become more westerly and should
see an increase in winds, becoming breezy by afternoon. With the
passage of the wave, temperatures are expected to cool by a couple
degrees although low humidities will remain. In fact, the inland
northwest and much of Washington has had some of the driest air across
the west since much of monsoon moisture has skirted the region.
Although some of this moisture will brush the southern Panhandle
for Thursday, and this with an increase in surface based
instability may bring another round of convection late Thursday
especially for the Camas Prairie into the south-central Panhandle
mountains. /Rfox.

Thursday night through Monday...after a small risk of
thunderstorms over the Camas Prairie Thursday evening, there is
little risk of any deep convection through the remainder of this
forecast period. The main story will be the reamplification of the
upper level ridge over the inland northwest. This ridge will result from
another 500 mb trough digging over the Gulf of Alaska. This should
result in warming temperatures through the weekend with widespread
high temperatures in the 90s over most valley location. All model
solutions show Saturday as being warmer than Friday however the ec
and GFS differ on whether or not Sunday is warmer than Saturday.
The ec says no, however the last few runs of the GFS said it would
be a little warmer. Given the continued amplification of the 500
mb pattern, we suspect the warmer solution is the more appropriate
one. The pattern begins to flatten a little by early next week as
a small chunk of the offshore trough tracks eastward through the
area but the pattern will likely amplify after that for renewed
warming. The situational awareness tool indicates a 99th
percentile temperature for Tuesday which would suggest this would
be the warmest day of the week. Not terribly confident this will
come to fruition, however we fully expect temperatures to remain
warmer than normal for this entire period. Any risk of monsoonal
moisture should remain well south and east of region through the
period. Fx

&&

Aviation...
12z tafs: light winds and VFR conditions are expected for much of
the upcoming period. Expect some upslope southeast winds at keat
this afternoon. Patchy smoke will linger near area wildfires in
the northen valleys. High clouds will increase across southeast
Washington and bring high overcast to klws and kpuw by this
evening. There is a small chance of thunderstorms from the blue
mtns to the Camas Prairie. /Rfox.

&&

Preliminary point temps/pops...
Spokane 93 64 91 60 89 62 / 0 0 0 0 0 0
Coeur D'Alene 92 59 90 57 89 57 / 0 10 10 0 0 0
Pullman 92 59 88 57 88 58 / 0 10 10 0 0 0
Lewiston 99 67 97 63 97 66 / 10 20 10 10 0 10
Colville 94 56 92 55 91 54 / 0 0 0 0 0 0
Sandpoint 89 52 88 50 88 49 / 0 0 10 0 0 0
Kellogg 89 58 88 56 87 56 / 0 10 10 0 0 0
Moses Lake 98 61 95 57 92 57 / 0 0 0 0 0 0
Wenatchee 96 68 92 63 91 63 / 0 0 0 0 0 0
Omak 97 63 95 61 93 59 / 0 0 0 0 0 0

&&

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

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