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fxus66 kotx 141151 
afdotx

Area forecast discussion
National Weather Service Spokane Washington
445 am PDT Mon Oct 14 2019

Synopsis...
a brief period of quiet weather returns Monday and Tuesday. A wetter
weather pattern is forecast for later in the work week with Rain,
Mountain snow, and breezy surface winds. Temperatures for the
weekend will be slightly cooler and below seasonal average.



&&

Discussion...
today and tuesday: a dry-stable northwest upper flow will precede
high pressure building into the inland northeast Monday and Tuesday.
As the ridge continues its eastward shift, an increasing southwest
upper flow will bring increased mid and high level cloudiness ahead
of the next incoming Pacific trough. A weak mid-level trough,
however, moving southeast across eastern Washington this morning
contributes to a broken layer of mid-level cloudiness lagging behind
the outgoing 500mb trough. This condition should dampen the
development of any low-level radiational cooling and reduce the risk
of widespread fog formation across region this morning. The valleys
of northern Idaho still have the best chance of fog lingering
through the morning. Some patchy fog is still possible along the
Purcell Trench into cda and could extend west into the Spokane area
before dissipating later this morning. With widespread clearing
continuing overnight Monday, there remains the risk of a repeat
possibility of fog formation Tuesday morning as radiation cooling
becomes more established throughout the region. Highs today and
Tuesday will be close to average and range from the mid 50s to mid
60s both days. Lows will be mostly in the 30s to low 40s with some
lows across the northern valleys dropping into the high 20s. /Aky

Wednesday through Sunday...once again models are a little slower
tonight. It still looks like a change to a more progressive
pattern with several short wave disturbances moving through the
region. The changes for tonight is that it looks like the first
short wave for Tuesday night/Wednesday will get a lot it's energy
sapped out of it as a bit stronger wave follows Wednesday
afternoon. Model guidance is also showing a wave Thursday night
and one more Saturday and Sunday. This will result in a cool, wet
and unsettled pattern through the week and into next weekend.

Precipitation will ease into the region Tuesday night and Wednesday
as the warm front sags east of the Cascades. And it now look like
the heaviest precipitation will be Wednesday afternoon and
Wednesday night ahead of the cold front. Snow levels will be up
around 7000 feet, with snow only at the higher elevations. Behind
the cold front snow levels will drop enough for accumulating snow
down to around 5000 feet. Some of the higher elevations of the
Cascades up near the crest could see moderate snow accumulations,
but overall accumulations of 3-5 inches in the mountains will be
possible through Thursday morning. Showers will remain in the
mountains Thursday afternoon but the remainder of the area should
see a brief break in the weather. The precipitation will be on
the increase Thursday night with the next wave. However, by this
time we lose the deep moisture tap. The mountains will still see
moderate precipitation amounts, but across the lower terrain
accumulations should be lighter. Snow levels drop down to
4000-5000 feet and the mountains will have the possibility of
picking up moderate accumulations of snow. Highs in the 50s to
lower 60s Wednesday and Thursday then fall into the 40s and 50s
the remainder of the week. Winds will be elevated and gusty each
day, with gusts 20-35 mph each afternoon.

Things get a little cluttered Saturday and Sunday, but it does
look like yet another disturbance will move into the region
Saturday and Sunday. Right now the track of this storm is along
the Cascades and south into Oregon, giving the inland northwest
just a glancing blow. There is more confidence that the
temperatures will remain cool with gusty winds. Time will tell so
stay tuned. Tobin

&&

Aviation...
12z tafs: confidence is high that all tafs should see VFR conditions
during the bulk of this forecast period. The tafs with the least
confidence are Coe and mwh due to the possibility of patchy fog
forming this morning. We think Coe has a better chance of fog due to
nearly saturated air, but mwh will also see a small chance due to
light winds and the possibility of strong radiational cooling. If
fog forms at either, we are confident it will break before 18z.
Otherwise main concern is the widespread mid-cloud deck with cigs
from 050-080 covering the eastern third of Washington and all of the Idaho
Panhandle. Model guidance is fairly certain this deck will thin and
break as drier air moves in this afternoon from the northwest. Fx

&&

Preliminary point temps/pops...
Spokane 54 34 59 40 57 39 / 0 0 0 10 30 60
Coeur D'Alene 52 33 60 40 58 40 / 0 0 0 10 20 70
Pullman 54 35 61 42 62 40 / 0 0 0 10 10 70
Lewiston 60 41 69 48 70 48 / 0 0 0 10 10 60
Colville 57 29 60 33 57 34 / 0 0 10 10 40 70
Sandpoint 52 33 57 38 57 40 / 0 0 0 10 30 80
Kellogg 50 36 59 43 61 43 / 10 0 0 10 10 80
Moses Lake 59 35 61 40 61 39 / 0 0 10 10 30 60
Wenatchee 58 40 58 45 58 43 / 0 0 10 20 50 60
Omak 58 37 57 40 55 40 / 0 0 10 10 50 80

&&

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

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