Weather

933 
fxus66 kpdt 212115 
afdpdt 


Area forecast discussion 
National Weather Service Pendleton or 
210 PM PDT Thursday Aug 21 2008 


Short term...tonight through Sunday...radar indicates isolated 
showers over the northeast Oregon and southeast Washington 
mountains. These showers will move east and out of the area over 
the next few hours. Skies will continue to clear this evening and 
with a drying air mass expect cooler temperatures tonight...forecast 
temperatures have been lowered a few degrees for tonight. Colder 
mountain valleys will see freezing or near freezing temperatures 
tonight. The ridge axis of a weak high pressure system will develop 
along the coast tonight and move east of the Cascades Friday. This 
will provide a stable air mass with mostly clear skies and light 
wind Friday. Friday night there will be a transition to southwest 
flow aloft ahead of the next frontal system approaching the coast 
from the west. Saturday and Sunday will be warm days with afternoon 
temperatures around 5 degrees above normal. Several models are 
showing a faster trend with the arrival of the next system...and 
there is a slight chance precipitation will reach the east slopes of 
the Washington Cascades as early as Sunday. 80 


&& 


Long term...Sunday night through Thursday...a relatively strong 
frontal system will push through the northwest on Sunday night and 
Monday. Although convection is not likely...there is a chance that 
this system will produce significant rain. Then as the front exits 
the area on Tuesday...drier conditions can be expected. 
However...the mild weather may not last long...since the models do 
hint at the possibility of another disturbance that will move 
through Washington on Wednesday. But due to uncertainty in 
long-range forecasts...have chosen to only include a slight chance 
of showers along the eastern slopes of the central Washington 
Cascades. Furthermore...cooler temperatures will accompany this 
upcoming active weather pattern due to northwesterly flow aloft and 
increased cloud cover. Calder 


&& 


Aviation...VFR conditions will prevail for the next 24 hours. 
Showers have moved out of the area and skies will gradually clear 
this evening and overnight. Breezy winds will become light by Friday 
morning. 82 


&& 


Preliminary point temps/pops... 
PDT 51 81 53 90 / 10 0 0 0 
alw 53 82 57 90 / 10 0 0 0 
psc 49 85 53 91 / 0 0 0 0 
ykm 46 81 51 87 / 0 0 0 0 
hri 47 83 51 91 / 0 0 0 0 
eln 45 81 50 87 / 0 0 0 0 
rdm 37 81 42 89 / 0 0 0 0 
lgd 42 79 46 89 / 10 0 0 0 
gcd 44 83 48 91 / 10 0 0 0 
dls 51 82 55 91 / 0 0 0 0 


&& 


PDT watches/warnings/advisories... 
or...none. 
Washington...none. 
&& 


$$ 


Ti:ggg 
for additional weather information, check our web site at... 
www.Weather.Gov/Pendleton 
80/82/82