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FXUS66 KPDT 260543

Area Forecast Discussion
National Weather Service Pendleton OR
1040 PM PDT Tue Apr 25 2017

.SHORT storm to impact the Pacific Northwest is now 
moving into the region. Rain is overspreading the forecast area 
this evening. Satellite imagery offshore looks fairly impressive
with long fetch of moisture and strong jet. Expect rain to continue
through the night and into Wednesday morning with weak warm advection
pattern. Cascades could see over an inch with northeast Oregon mountains
a half inch. Cold front will then move through later Wednesday. Steady
precipitation will change to showers and westerly winds will increase
with surface high pressure building in. Expect breezy to windy conditions
to continue into Thursday. 94

.AVIATION...06z tafs. Occasional rain tonight into Wednesday morning 
with ceilings 030-060. Winds 5-15kt. Rain tapering off Wed afternoon 
after cold frontal passage. Ceilings 040-080. Winds increasing to 15-


.PREV DISCUSSION... /issued 200 PM PDT Tue Apr 25 2017/ 

SHORT TERM...Tonight through Friday...An upper level storm system 
will move across the region tonight through Wednesday with another 
storm moving across the area Thursday as the upper flow transitions 
to nwly by the end of the work week. Rain is currently overspreading 
western Oregon and the precipitation will move into our forecast 
area this evening. There could be a brief break in the rain later 
this evening before another round of mostly rain moves in ahead of a 
cold front late tonight. The precipitation will be heaviest in 
Oregon. A good dose of rain will occur in Oregon and extreme se 
Washington on Wednesday ahead of the cold front. QPF amounts could 
reach or exceed .5 inches in the mountains. It will become 
windy/very windy with the frontal passage. Have issued Wind 
Advisories for the Kittitas Valley and Simcoe Highlands for gusty w-
nw winds. It is quite possible that a few more lower elevation zones 
will need to be added for wind highlights. Once the front clears the 
area Wednesday evening precipitation will become more showery 
through Thursday with favored upslope regions of the eastern 
mountains receiving the most rain/snow. There could be several 
inches of snow for the Northern Blue Mountains above 4000-4500 feet 
from Wednesday evening through Thursday night. It is possible that 
winter highlights will be needed. By Friday a drier northerly flow 
will develop with decreasing chances for showers.  78

LONG TERM...Friday night through Tuesday...High pressure will build 
into the region late Friday bringing showers to an end. The ridge 
will flatten Saturday night allowing a weather system to impact the 
forecast area Sunday with some precipitation and breezy conditions. 
Following this system we will be under a northwest flow which will 
mainly impact the Washington Cascades and the northern Blue 
Mountains with some lingering showers.  


PDT  44  57  40  55 /  70  70  20  30 
ALW  46  58  43  58 /  70  70  40  40 
PSC  47  63  44  62 /  50  40  20  20 
YKM  40  63  39  59 /  60  40  10  10 
HRI  45  61  43  59 /  60  60  10  20 
ELN  42  58  39  54 /  60  40  10  10 
RDM  38  54  30  51 /  70  80  10  20 
LGD  40  52  37  49 /  80  80  30  40 
GCD  35  52  34  50 /  80  90  30  40 
DLS  45  59  45  57 /  80  70  20  20 


WA...Wind Advisory from 11 AM Wednesday to 9 PM PDT Thursday for 

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