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Area forecast discussion 
National Weather Service Spokane Washington
215 PM PST sun Feb 7 2016

Synopsis...
strong high pressure will develop tonight and persist into
Wednesday. Dry and mild conditions are expected for the first half
of the week. A more progressive and unsettled pattern will return
late this week bringing a chance of light rain Thursday in the
Cascades and over the rest of the region Friday through the weekend.

&&

Discussion...
tonight and monday: a ridge of high pressure will strengthen in
over the region the next 24 hours. Mid level moisture riding up
over the ridge this afternoon will decrease through the evening. A
few flurries may be possible over the northern Panhandle before
skies clear out overnight. Strong inversions will develop with
patchy fog possible for many of the Mountain Valley locations.
This inversion will be even more difficult to break on Monday
compared to today. The fog that does develop may burn off a bit
later in the day and keep surface temperatures in the upper 30s
to low 40s for the mountain valleys. /Svh

Monday night through Thursday...this period will be characterized
by a strong upper level ridge...light winds...cool morning low
temperatures with varying fields of fog and low clouds each
morning and a general break out over most of the region during the
afternoon with high temperatures rising above normal for most
locations. The Palouse and l-c valley will be the clearest and
mildest regions with a general easterly gradient keeping fog
scarce and promoting well above average temperatures due to
downslope compressional warming each day. The deep basin and
Cascades valleys where the easterly gradient will transport and deposit
the more stagnant air will see the most fog and low clouds and the
weakest daily clearing potential below 4000 feet. Thursday the
ridge axis will begin to shift eastward...and allow a more moist
Pacific southwesterly flow to take over. Precipitation chances
will begin to increase over the Cascades and northern
mountains...but with little impact over the lion's share of the
forecast area beyond increasing high clouds.

Thursday night through Sunday...models are in pretty good
agreement for the remainder of the extended forecast period.
Thursday night the upper level rideg axis continues to migrate
east and out of the region with increasingly moist southwesterly
flow becoming established. Precipitation chances will begin to
spread through the forecast area from west to east. Snow levels
will remain quite high in this southwest warm advection
scenario...but the colder boundary layer air trapped in the
Cascade valleys may allow some freezing rain as early as Thursday
morning and a better chance on Friday morning. Friday will be a
transition day between the dry ridgy weather regime and a more
active Pacific storm regime. A cold front with a significant
potential fro valley rain and mountain snow will cross the region
on or about Friday night and Saturday. This evolution will scrub
the region by wiping out any lingering inversion and allow a
lowering of snow levels for subsequent storms. Another and
possibly better organized storm may approach the region on
Sunday...but model details are sketchy and unreliable at this
time. /Fugazzi



&&

Aviation...
18z tafs: shallow fog around the Spokane area will result in vlifr
conditions through 19z, but should then quickly burn off for the
afternoon. High pressure will continue to build in today. High and
mid level clouds will filter in over the ridge with cigs generally
remaining above 8 kft agl. These clouds will thin out tonight with
more shallow fog possible around the region, especially near water
bodies and in deep valleys (including ksff). /Svh



&&

Preliminary point temps/pops...
Spokane 27 44 30 47 31 46 / 0 0 0 0 0 0
Coeur D'Alene 28 46 30 47 31 47 / 10 0 0 0 0 0
Pullman 31 51 32 53 34 53 / 0 0 0 0 0 0
Lewiston 35 54 34 54 37 55 / 0 0 0 0 0 0
Colville 25 41 26 41 29 43 / 10 0 0 0 10 0
Sandpoint 27 42 29 43 31 44 / 10 0 0 0 10 10
Kellogg 28 45 29 48 32 46 / 10 0 0 0 0 0
Moses Lake 28 45 29 46 31 46 / 0 0 0 0 10 0
Wenatchee 30 40 30 41 31 44 / 0 0 0 0 10 0
Omak 25 39 26 39 28 40 / 10 0 0 0 10 0

&&

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

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