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fxus66 kpdt 230948 

Area forecast discussion
National Weather Service Pendleton or
248 am PDT Mon Sep 23 2019

Short term...
today through Wednesday night... mainly dry conditions have
developed in the wake of yesterdays storm system with scattered to
widespread cloudiness persisting. This will likely continue
through the morning hours as weak lift continues along the
northern periphery of a closed low now digging into the Desert
Southwest. As this feature departs, upper ridging will build in
across southern Oregon and northern California into tonight. This
ridge will ultimately be shunned southward, however, by a series
of shortwaves moving through rather fast west/northwest flow
across the Pacific northwest. Each of these waves will bring bouts
of increased mid and high cloud cover, and chances for showers
mainly in the Washington Cascades and their east slopes. This
pattern will support rather breezy conditions both today and
tomorrow, with a tightening pressure gradient and rather strong
winds just off the surface. The typically windier locations of the
Columbia Gorge and lower Columbia Basin will likely see wind
gusts in the 25 to 35 mph range, which is shy of advisory
criteria, but it will certainly be noticeable for those
traveling. Temperatures to remain rather mild each afternoon with
highs generally in the 60s and 70s and lows in the 40s and 50s.

Long term...
Thursday through Sunday... a frontal system will be pushing
through eastern Washington and Oregon on Thursday with some light
precipitation and breezy to locally windy conditions. Cooler air
arrives behind the front with snow levels lowering to 5000-6000
feet by Friday morning with some lingering showers. Overall
pattern from Friday through the weekend shows an upper level low
in southern Canada by Friday night that drops south into eastern
Washington and Oregon through the weekend, but models continue to
show varying amounts of moisture and differences with timing.
Scattered showers can be expected through the period with some mix
of rain and snow during the overnight hours for the mountains.
This pattern will allow for some of the coldest air so far this
fall with frost and some freezing temperatures possible beginning
Friday morning through the weekend with daytime highs topping out
well below normal for late September.

aviation...12z tafs. VFR conditions should prevail through the
period. Some lingering stratus 030-050k ft above ground level across central
Oregon and the Blue Mountains through 18z with mid and high level
clouds increasing over southern Washington and northern Oregon. A
weak disturbance will be passing through mainly Washington late
today and tonight taf sites should only see mid and high level
clouds. Surface winds: variable less than 10 kts, becoming west-northwest
5-15 kts with local gusts to 20 kts after 18z.


Preliminary point temps/pops...
PDT 69 51 74 45 / 0 0 0 0
alw 73 55 77 50 / 0 0 0 0
psc 74 55 79 51 / 0 0 0 0
ykm 72 49 76 45 / 10 10 0 0
hri 74 53 79 48 / 0 0 0 0
eln 66 50 70 47 / 10 10 10 0
rdm 69 46 74 43 / 0 0 0 0
lgd 69 50 72 45 / 0 0 10 0
gcd 71 48 76 45 / 0 0 0 0
dls 72 56 77 53 / 0 10 10 0


PDT watches/warnings/advisories...

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