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Area forecast discussion 
National Weather Service Spokane Washington
250 am PDT Friday Oct 24 2014

Synopsis...
breezy and unsettled conditions will continue for the rest
of today but be on the decrease tonight and into tomorrow. This is
only temporary as rain is expected to return Friday night and
Saturday. A strong cold front passage Saturday night and Sunday
will produce very windy conditions with gusts in excess of 40 mph.
The pattern will continue to be active into early next week. This
includes the potential for widespread rain into early next week as
moisture associated with former typhoons makes its way toward the
Pacific northwest.

&&

Discussion...
today through tonight...looks like this period will see a Little
Break in the action in regards to our recent string of wet weather.
The anomalously moist atmospheric river has temporarily dipped
south of our forecast area. As of 2am...about the only weather
action was a blanket of high level moisture covering most of the
region. This cloud cover was associated with the 130-150kt upper
level jet. This dry respite will gradually come to an end this
morning in response to deep upstream trough centered near
35n/139w. Models in good agreement that as this trough moves
closer to the coast...the atmospheric river will buckle northward
as a warm front and push steadily across the Oregon/Washington
border. This transition will be accompanied by backing mid-level
flow (southerly winds)...leading toward a significant increase in
isentropic ascent and moisture advection. This will result in an
increasing chance of precipitation. By midday most of the
precipitation will be just south of our forecast area...however
some light rain could creep into the Blue Mountains and Camas
Prairie. By the latter half of the day...there is good model
agreement that the northern edge of the preciptiation will lie
approximately from Pullman to Moses Lake.

The front will continue to surge northward overnight...reaching
the Canadian border well after midnight. Based on the good
moisture availability and moderate isentropic ascent...most areas
will receive some precipitation. Confidence is highest however
near the Cascades...as the 850-700 mb layer takes on a well
defined southeast-east wind regime. This will lead to good
orographic ascent which will only be bolstered by strong
divergence aloft. Categorical pops will be justified for locations
west of a Republic to Wenatchee line...and quantitative precipitation forecast totals will likely
range from a quarter to half inch. Snow levels will likely be
fairly high...ranging from 5.5-6k feet. This should not pose any
travel problems...however some snow can be expected to fall late
tonight over the highest parts of the north Cascades Highway.
While the precipitation really gets going late tonight over
locations near the Canadian border...it will begin to taper off
near the Oregon border as the dry slot move in behind the warm
front. Fx

Saturday through Monday night: an upper level trough and surface
low will approach the southern Oregon coast Saturday. This weather
disturbance will bring an increase in cloud cover through the day.
As the surface low moves up the coast through the day and then
pushes inland through the evening our chance of precipitation will
increase. Have increased chance of precipitation for most
locations as many locations should receive at least 0.01 of
precip as this feature moves through. Even normally dry locations
such as the basin and East Slope of the Cascades valleys could see
rain given the decent southeast upslope flow ahead of the cold
front.

..breezy to windy conditions expected Saturday night and Sunday...

Winds associated with the cold front will be quite strong.
Saturday evening southerly winds 10 to 20 mph will be common
across most of the Columbia Basin and into the Palouse and
Spokane/cda areas. Those winds will increase through the overnight
hours and into Sunday morning to 20 to 30 mph with gusts to 40 or
45 mph. Right now the strongest winds look to stretch from the
Blue Mountains up through the Palouse. Winds will slowly decrease
through Sunday afternoon and into the evening hours as the surface
low weakens and continues to move east across southern Canada.

Sunday the chance of precipitation will decrease through the
evening hours. The exception to this will be the Cascade crest and
Idaho Panhandle where showers will likely continue. A Flat Ridge
moves into the inland northwest Monday ahead of the next
potentially big soaker. Chance of precip will increase through the
overnight hours and into Tuesday morning, especially along the
Cascade mountains and nearby valleys as the next weather system
moves onto the West Coast.

Temperatures will start out at or above average on Saturday and
then drop to near average readings by Sunday and then to slightly
below average readings by Monday. /Nisbet

Tuesday through thursday: the models are depicting a shortwave
trough pushing through the region followed by a weak ridge
building into the region for this period. For Tuesday, widespread
rain is expected in the morning. Precip chances will decrease from
west to east as the period progresses into Wednesday leaving only
the Idaho Panhandle with high potential to receive rain. Model
agreement on Thursday is not high but they are indicating a low
in the Gulf of Alaska beginning to press into the Pacific
northwest and bringing some precip to the Cascades. Light winds
associated with this pattern has potential for morning fog int he
northern valleys. Temperatures will still be above normal with
highs in the mid 50s to low 60s and lows in the upper 30s to mid
40s. /Jdc

&&

Aviation...
06z tafs: the stalled frontal band has moved southeast, ending
precipitation across southeast Washington and the Idaho Panhandle.
Abundant low level moisture available from recent rainfall will
promote formation of fog and low clouds overnight and into Friday
morning. Models show this front will lift back north from Oregon
and push into southern Washington and the central Panhandle of Idaho as a
wet warm front Friday afternoon/evening. /Ek

&&

Preliminary point temps/pops...
Spokane 55 44 65 43 52 36 / 0 60 30 80 30 10
Coeur D'Alene 55 42 65 42 51 34 / 10 50 30 90 30 20
Pullman 55 45 68 42 49 38 / 30 50 20 80 30 20
Lewiston 59 44 72 47 56 41 / 40 50 10 60 20 20
Colville 54 42 62 45 52 35 / 10 70 30 80 50 20
Sandpoint 53 40 61 42 48 34 / 10 70 30 90 50 30
Kellogg 52 41 64 40 45 34 / 10 60 20 90 40 30
Moses Lake 57 45 60 45 59 37 / 10 80 20 30 10 10
Wenatchee 57 44 57 43 55 38 / 10 80 60 40 10 10
Omak 56 42 55 43 54 35 / 10 90 50 50 30 10

&&

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

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