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Area forecast discussion 
National Weather Service Spokane Washington
435 am PDT Friday Sep 19 2014

Synopsis...
a strong high pressure ridge will return today and promote warm
and dry weather through Tuesday. High temperatures Sunday and
Monday should be ten degrees above normal. The breakdown of this
ridge...and a return to cooler conditions...will begin Wednesday.
However...precipitation and much cooler weather is not expected
until Wednesday night or Thursday for most communities since the
front will likely move very slowly east.

&&

Discussion...
today through Saturday...the upper trough that brought isolated
showers to the Idaho Panhandle overnight has moved east of the
region today, making way for a building ridge of high pressure. A
weather disturbance will brush the northern border today and may
result in an isolated shower or two but this will be pushed
farther north by the retreating jet stream by this afternoon. The
building ridge will bring dry conditions and warming temperatures
to the inland northwest Saturday. Clear skies and light winds
could allow a return of morning fog to the northeast valleys,
mainly in the vicinity of rivers and lakes. /Kelch



Sat nt through Wed morning: with the high amplitude upper ridge
axis over the Idaho Panhandle Sat nt moving well east by Mon, the
door will be open to the ern Pacific and the offshore trough
approaching the region. The least confident part of the fcst will
be timing the ejection of a number of small waves that eject NE
into the region out of the trough. The first wave will be very
weak and, given the lack of deep instability over a dry sub-
cloud layer, is not expected to produce much more than some
clouds for Mon nt. The first real cold front is expected to make
landfall tues nt and Wed morning along the Pacific NW coast.
We've been favoring a slower trend of this cold front as far as
its ewd progression based on model trends and pattern recognition
applied to the north-south shearing offshore trough. The
downstream effects of this shearing will be a more meridional
steering flow over ern WA and north Idaho, leading to a more
persistent thermal ridge and warm, dry wx likely extending into
Wed. For now, we limited the rain through Wed morning to the
Cascades. Bz

Wednesday through friday: a cold front will begin to push into the
region as the ridge pattern will shift to the east. The models are
having issues with the timing of the this system as they have
continued to push this pattern further back from previous runs.
Once the front pushes through the region, rainshowers will impact
most of the region and temperatures will return to season normals
of around 70. /Jdc

&&

Aviation...
12z tafs: winds will continue to diminish but will remain elevated
at keat. Upslope flow into the kgeg-kcoe area has not resulted in
stratus development this morning so development for Saturday
morning is unlikely. VFR conditions are expected at all taf sites
for the next 24 hours. /Ek



&&

Preliminary point temps/pops...
Spokane 76 51 81 52 84 56 / 0 0 0 0 0 0
Coeur D'Alene 75 49 80 49 84 53 / 10 0 0 0 0 0
Pullman 76 47 82 49 87 52 / 0 0 0 0 0 0
Lewiston 82 55 87 56 89 59 / 0 0 0 0 0 0
Colville 79 46 85 47 86 47 / 10 0 0 0 0 0
Sandpoint 71 43 77 44 79 45 / 10 10 0 0 0 0
Kellogg 71 49 78 48 81 52 / 10 0 0 0 0 0
Moses Lake 83 50 86 54 88 56 / 0 0 0 0 0 0
Wenatchee 82 56 85 58 87 61 / 0 0 0 0 0 0
Omak 81 49 85 50 87 54 / 0 0 0 0 0 0

&&

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

$$

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