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000 
FXUS66 KPDT 170526
AFDPDT

Area Forecast Discussion
National Weather Service Pendleton OR
1022 PM PDT Mon Oct 16 2017

.SHORT TERM...Clear skies over the forecast area this evening.
Clouds associated with approaching frontal boundary still off to
the northwest. Will see increasing clouds across the Washington 
Cascades and eventually into the northern Columbia basin late.
Further south should remain clear overnight. Highs today were 5-10
degrees warmer than Sunday so expect a milder night with lows in
the 30s to lower 40s for most locations. Cold front moves slowly
across the region Tuesday. Best area of rain will be over the 
Washington Cascades. Much less over the Blues with downslope flow
likely keeping the Columbia basin dry. Main impact will be
increasing winds. Strong westerly winds aloft will move through 
during the day and expect mixing down off the Cascades. Afternoon
winds will likely be in the 20-40 mph range. Blowing dust possible
in the basin. 94

.AVIATION...06z tafs. Clear skies overnight with winds less than 
10kt. Increasing clouds Tue with a frontal passage during the day. 
Ceilings bkn 050-100. Westerly winds increasing late morning through 
the afternoon becoming 15-30kt. 

&&

.PREV DISCUSSION... /issued 500 PM PDT Mon Oct 16 2017/ 

SHORT TERM...Tonight through Wednesday night...The flat upper level 
ridge over the Pacific Northwest will flatten further tonight as a 
disturbance moves towards the region for the Gulf of Alaska. This 
disturbance will swing across British Columbia and Washington 
Tuesday. As such, will see mainly fair and dry conditions over much 
of the area tonight. Will see clouds increase overnight over south-
central Washington. Also should see some light precip begin to move 
into the Washington Cascade east slopes, mainly after midnight. The 
system Tuesday will push a cold front across the area. The main 
impact with this frontal passage will be increasing winds across the 
area, especially the Columbia Basin. Winds in the Basin and adjacent 
valleys will generally run 20 to 30 mph. Could see winds locally of 
30 to 35 mph with gusts around 45 mph in the Yakima valley and the 
Lower Basin in Washington, as well as the Kittitas valley. Thus will 
issue wind advisories for these areas. Winds in the Columbia Basin 
could cause some patchy blowing dust Tuesday afternoon and early 
Tuesday evening. The bulk of the precip with this system will occur 
along the Washington Cascade east slopes. The Blue Mountains could 
see decent chances of precip Tuesday evening. A warm front will 
bring precip to portions of the area, especially the Washington 
Cascade east slopes, Wednesday. The precip will persist over the 
Washington Cascade east slopes Wednesday night, but will largely end 
elsewhere. Low temps will generally be below seasonal again tonight. 
Otherwise temps will be above seasonal Tuesday through Wednesday 
night. Snow levels will run 5500 feet or higher through the period. 
90 

LONG TERM...Thursday through Monday...Longwave upper trough 
approaches the coast Thursday and pushes a cold front into CWA 
Thursday afternoon bringing rain through Thursday night. Friday will 
be windy and rainy while the cold front sweeps through the region 
and moves into Idaho by daybreak Friday morning. The upper trough 
moves across the forecast area during the day on Friday resulting in 
unsettled conditions over the eastern Oregon mountains during the 
day on Friday. Friday night the region will be between weather 
systems with rain shadowing at lower elevations due to a ridge  of 
high pressure building over the pacific Northwest ahead of a wet 
warm front that moves into central and north central Oregon Saturday 
morning. The warm front and attendant rain spreads over the rest of 
the forecast area Saturday afternoon. Rain totals on Saturday will 
be around 0.25-0.35 inches at lower elevations and near 0.50 inch of 
rain in the mountains. Snow levels lower to 4500 feet in the Blue 
Mountains on Friday. The warm front at associated rain/mountain snow 
remains over the forecast area Saturday night and Sunday for 
additional precipitation.  Polan

&&

.PRELIMINARY POINT TEMPS/POPS...
PDT  41  68  44  68 /   0  10  20  20 
ALW  46  69  50  68 /   0  20  30  30 
PSC  36  70  41  67 /   0  10  10  20 
YKM  33  69  38  63 /   0  20  10  20 
HRI  34  71  42  69 /   0  10  10  20 
ELN  34  65  37  59 /   0  20  10  30 
RDM  34  72  38  72 /   0   0  10  10 
LGD  34  70  44  69 /   0  10  20  20 
GCD  35  70  40  70 /   0   0  10  10 
DLS  40  67  46  68 /   0  20  20  20 

&&

.PDT WATCHES/WARNINGS/ADVISORIES...
OR...None.
WA...Wind Advisory from noon to 8 PM PDT Tuesday for WAZ027-028.

     Wind Advisory from 2 PM to 8 PM PDT Tuesday for WAZ026.

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