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Area forecast discussion 
National Weather Service Spokane Washington
1104 am PDT Thursday Aug 27 2015

Synopsis...
a southwest wind will increase in the afternoon which should help
to disperse the smoke a bit, but also brings a cause for concern
on area wildfires. A very strong cold front is expected to arrive
on Saturday, bringing windy conditions to the inland northwest but
also some much needed rain to portions of the area. Blowing dust
will be a concern by Saturday afternoon. A cooler and occasionally
breezy regime with some shower activity will persist through the
next week.

&&

Discussion...
today and tonight: we remain under high pressure with a low
pressure system moving closer to the West Coast. Some clouds will
move through the area this morning. Inversions will remain strong
through the morning and thus keep the smoke across most of the
lower elevations. This afternoon winds will increase from the
southwest. Widespread winds of 10 to 15 mph will be likely across
most locations. Portions of the Columbia Basin, Waterville
Plateau, western Spokane co as well as southern Pend Oreille,
Stevens and Ferry counties will see slightly stronger winds.
Sustained southwest winds 13 to 18 mph with gusts up to 25 mph
combined with low daytime relative humidities will create critical
fire conditions for existing fires. Will continue the red flag
warning from 1 to 8 PM today. With the increased winds we should
see the smoke disperse or thin during the afternoon and evening
hours. The winds will begin to subside around sunset and the smoke
will likely return overnight. Clouds will increase from the west
overnight as the low pressure system moves closer to shore.
/Nisbet

Friday through Wednesday...it appears some major changes are afoot
in the extended term with all the latest models coming on board
with a depiction of a more progressive...cooler and potentially
wetter pattern...at least wetter for some portions of the
forecast area. While Friday appears to be another warm and largely
dry day over the region...by Friday night and Saturday the large
offshore closed low visible on satellite will eject inland across
the region bringing some much needed rain right where we need
it...mainly in the Cascades but also a growing chance of scattered
to widespread showers across the northern tier zones. It is not
yet clear whether enough rain will fall in enough places to make a
huge difference in the fire fighting efforts but the cooler
temperatures and what precipitation does reach the ground will
help somewhat. The best guess at this time for Friday night
through Saturday appears to support a half an inch to over 1 inch
in the Cascades dependent on elevation and distance from the
crest...and anywhere from a tenth to a quarter of an inch across
the northern tier zones.

More rain is possible with a series of follow up waves and and
fronts through the week as a general troffy pattern becomes
established. Confidence is quite high that the entire period after
Friday will be cooler than average. The precipitation outlook is
a bit less certain after Saturday but at least a few mountain
showers every day is a plausible scenario.

The main threat issue will be breezy to windy conditions
particularly on Saturday with the main leading cold
front...especially over the basin but the gradient development and
especially the gust potential from mixing in the Post frontal
air mass will promote 20 to 30 mph gusts over exposed terrain
through out the region. Occasionally breezy conditions will linger
through much of the week in a cooler and more progressive maritime
regime. /Fugazzi

&&

Aviation...
18z tafs: the region will be sandwiched between low pressure in
the eastern Pacific and high pressure over the rookies. A cold
front will linger offshore through Friday morning. The proximity
of the front will promote better mixing today. This is expected to
result in at least some improvement to the smoke across the basin
and for many of the taf sites. Klws will have a more difficult
time mixing out today and is expected to remain MVFR through at
least this afternoon. Wind gusts to between 15-22 kts will be
possible in the afternoon. /Svh

&&

Preliminary point temps/pops...
Spokane 89 61 85 63 75 53 / 10 0 10 10 30 20
Coeur D'Alene 88 57 85 59 79 51 / 10 0 10 10 30 20
Pullman 87 55 86 59 77 51 / 0 0 10 10 20 20
Lewiston 92 64 89 66 86 58 / 0 10 10 10 20 10
Colville 90 55 84 56 76 49 / 10 0 10 20 50 30
Sandpoint 86 51 83 54 79 48 / 10 0 10 20 40 30
Kellogg 86 55 86 56 76 48 / 10 0 10 10 30 20
Moses Lake 92 60 86 62 76 55 / 10 0 10 20 40 30
Wenatchee 91 67 84 65 73 57 / 10 0 10 40 50 30
Omak 89 61 83 62 73 51 / 10 0 10 50 70 40

&&

Otx watches/warnings/advisories...
Idaho...none.
Washington...red flag warning from 1 PM this afternoon to 8 PM PDT this
evening for East Washington central Cascade valleys (zone
677)-East Washington northeast (zone 686)-East Washington
northern Columbia Basin (zone 673)-East Washington Okanogan
Highlands (zone 687)-East Washington Okanogan/Methow
valleys (zone 684)-East Washington Palouse and Spokane area
(zone 674).

&&

$$

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