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fxus66 kotx 202335 
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Area forecast discussion
National Weather Service Spokane Washington
435 PM PDT sun Aug 20 2017

Synopsis...
high clouds will clear overnight. Skies should be favorable for
viewing the eclipse Monday morning, however there may be some
smoke in the northern valleys. Tuesday and Wednesday will be quite
warm with afternoon temperatures in the upper 80s to upper 90s.
A vigorous cold front passage has the potential to produce
thunderstorms Wednesday night into Thursday, mainly over the
north Idaho Panhandle. This will be followed by gusty west winds
Thursday.

&&

Discussion...
tonight through Tuesday night: the upper level ridge is building
along the West Coast this afternoon and will move inland Monday.
Temperatures will continue to warm...into the mid 80s to low 90s
Monday and 90s on Tuesday (the warmest day of the week). Temps top
out Tuesday about 10 degrees above average for this time of the
year. The ridge will then begin to shift east Tuesday night ahead
of the next weather system set to move into the Pacific northwest.
Southwest winds around Spokane/Deer Park and Coeur D'Alene will
continue at around 10 mph with gusts 15-20 mph, but should subside
early this evening. Otherwise winds will remain light and under
10 mph.

*Eclipse: sky conditions for the eclipse Monday morning are
expected to be sunny to mostly sunny with some high cirrus across
northern Washington and Idaho. Winds will become light and
variable...similar to what we would see at night. /Nisbet

Wednesday through Thursday night: significant changes in the weather
occur. Primary issue of note would be the windy/gusty conditions
brought about by a large trof/cold front passage on Thursday which
will result in blowing dust in some parts of the Columbia Basin. In
addition there are is a mention of the potential for thunderstorms
with this transition, both ahead of the incoming trof with the
southwest flow bringing them up with a robust storm motion from
southwest to northeast at 20 mph Wednesday up from Oregon and over
the Blue Mountains, through the Washington and Oregon Palouse and
points to their south, and into the Idaho central Panhandle
mountains. Thunderstorm potential along with storm motion increases
Wednesday night into Thursday to southwest to northeast at 30 mph
ahead of the cold front. In addition the potential for thunderstorms
increases Wednesday night into Thursday for extreme eastern
Washington and north Idaho. The most substantial conditionally
unstable air left in the region in the wake of the cold front
passage remains to the north over British Columbia and another trof
extending from it brushes over locations not too far from the border
so some mention of thunderstorms remains near these northern
locations along with portions of north Idaho where the upslope
prevailing southwest flow could still provide the lift and triggers
for convection there. A benefit of the prevailing southwest winds
during this time interval is that they would not bring smoke in from
southern British Columbia fires but could stir smoke around our area
and perhaps bring in some from Oregon.

Friday through sunday: ridging moves into the area allowing for a
warming and drying trend with a generally dry forecast. Winds should
be more diurnally driven and as such considerably lesser in
comparison to Thursday. /Pelatti

&&

Aviation...
00z tafs: smoke will continue to impact northern Washington and Idaho
valleys, but not the main taf terminals. Bkn-ovc high clouds
are currently moving across the region and will be exiting
overnight. During the eclipse (16-19z), expect light variable
winds with a very high few-sct300 cloud deck. Winds will be light
for all terminals through 00z Tue. /Sb



&&

Preliminary point temps/pops...
Spokane 58 86 62 92 63 89 / 0 0 0 0 0 10
Coeur D'Alene 53 87 56 92 58 89 / 0 0 0 0 0 10
Pullman 52 87 55 92 57 89 / 0 0 0 0 0 10
Lewiston 59 93 63 99 66 93 / 0 0 0 0 0 20
Colville 51 88 53 92 54 91 / 0 0 0 0 0 10
Sandpoint 47 85 50 91 51 86 / 0 0 0 0 0 10
Kellogg 51 85 55 91 56 86 / 0 0 0 0 0 10
Moses Lake 56 91 57 95 59 93 / 0 0 0 0 0 10
Wenatchee 63 90 66 95 66 91 / 0 0 0 0 0 10
Omak 60 92 61 96 62 94 / 0 0 0 0 0 10

&&

Otx watches/warnings/advisories...

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