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FXUS66 KPDT 181958

Area Forecast Discussion
National Weather Service Pendleton OR
1258 PM PDT Wed Sep 18 2019

.SHORT TERM...Tonight through Saturday. Upper level low continues
to spin overhead and will slowly move eastward overnight. 
Scattered showers and a few thunderstorms will continue through 
the early evening before gradually tapering off after sunset. If 
any thunderstorms are able to develop, there could be some small 
hail/graupel mixed in with the rain. Much of the trough axis will 
be east of the area by Thursday and Friday;however, some energy 
rotating around the back side may bring additional showers and 
possibly a thunderstorm to the higher terrain of the Ochoco-John 
Day Highlands northeastward through the Blue/Wallowa Mountains. A 
few light showers will also be possible for the Cascade crests. 
Upper level ridging is still expected to arrive for Saturday, 
finally giving us a break from the unsettled weather that has been
common this week. Along with the drier weather, more sunshine is 
expected as temperatures warm into the middle to upper 70s for the
lower elevations with 60s expected for the mountains. Richards

.LONG TERM...Saturday night through Wednesday...Models in good 
agreement to start the long term. Saturday night transient ridging 
quickly shifts east as a strong upper-level trough slides south 
along the BC coast and begins to work into the PacNW. On Sunday an 
associated cold front will sweep through the inland NW as a closed 
upper low forms and moves overhead. Expect scattered showers with a 
few thunderstorms as well, however instability is quite modest. 
Beyond Sunday, models begin to diverge quite a bit. The general 
trend through is for the closed low to cutoff from the main flow and 
settle somewhere south of our area, while an upper high over the 
eastern Pacific tries to nudge eastward over the cutoff into the 
PacNW. Expect drier conditions early to mid next week with either 
ridging over the region or zonal to northwest flow. If ridging 
unable to establish over the area, there could be some increased 
cloud cover and possible mountain showers with Pacific moisture 
riding the zonal to northwest flow. Some breezy winds possible with 
frontal passage on Sunday, otherwise relatively light winds 
expected. Below normal temps on Sunday with the low/trough overhead 
with highs in the 60s to low 70s. Warming a bit early to mid next 
week and becoming near to slightly above average with highs in the 
upper 60s to upper 70s.


.AVIATION...00Z TAFs...Scattered showers and isolated thunderstorms 
through this evening. Mainly VFR conditions with ceilings bkn 5-8 
kft, however MVFR CIGs/VIS under heavier showers/storms along with 
mountain obscuration possible. Storms could produce small hail and 
gusty winds. Otherwise, expect wind 10kts or less through tomorrow. 
Winds pick up a bit at DLS tomorrow afternoon 15g20-25kt. Between 04-
08Z, showers/storms should have ended at the terminals, although 
could linger over the mountains across central/northeast OR.


PDT  48  68  49  69 /  30  20  10  10 
ALW  49  70  51  71 /  20  30  10  10 
PSC  52  75  53  75 /  20  10   0  10 
YKM  46  72  50  72 /  20   0  10  10 
HRI  50  74  53  74 /  20  10   0  10 
ELN  46  69  50  69 /  30   0  10  10 
RDM  41  64  42  64 /  50  10  10  20 
LGD  44  62  44  63 /  50  40  10  20 
GCD  44  60  44  60 /  60  50  20  20 
DLS  50  71  54  70 /  30  10  10  20 



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