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Area Forecast Discussion
National Weather Service Pendleton OR
830 AM PDT SAT JUL 30 2016

.SHORT TERM...Today through Monday...No sig changes needed to
current forecast. First mini surge of modified Pacific air has
entered the forecast area. Mesonet obs show midslope and ridgetop
temperatures have cooled significantly since Friday morning. This
combined with the increasing supply of Pacific air will act to lower
max temperatures 5 to 10 degrees from Friday. Current dry soil
conditions and increasing winds may begin moving loose dirt, so
patchy blowing dust introduced in the overnight forecast looks good.
Cooling trend continues Sunday with less wind and then levels off
for Monday as flow becomes more southwest ahead of an upper level
trof.

&&


.AVIATION...18z Tafs.  VFR conditions will prevail with mostly clear
skies. As dry cold front moves through area winds will continue to
increase with west winds 15 to 25 Kts with gusts to 30 Kts at
KDLS...KPDT...KALW decreasing after midnight.  Other sites will see
west winds 10 to 20 kts. 93


&&

.FIRE WEATHER...Red Flag Warnings are in effect through this evening
for gusty winds and low relative humidity for the fire zones
covering the Eastern Columbia River Gorge and the east slopes of the
Northern Oregon Cascades (fire zones WA/OR639 and OR610). Red Flag
Warnings are also in effect from 1 PM to 9 PM today for the Columbia
Basin zones down to Central Oregon (WA675, WA/OR639, and OR640).
Winds will decrease for Sunday...thus even with minimum RHs between
10 and 20 percent for most lowland locations...the potential for
extreme fire behavior will diminish.

&&

.PREV DISCUSSION... /issued 300 AM PDT SAT JUL 30 2016/ 

SHORT TERM...Today through Monday afternoon...A dry cold front will
usher in a marine push that will transport slightly cooler pacific
air into the region for some relief from the hot temperatures that
occurred yesterday. Highs on today will be 7-9 degrees cooler than
Friday's highs. Increasing pressure gradients associated with the
cold front will bring breezy conditions in the Lower Columbia Basin
to north central Oregon this afternoon into this evening with
windy conditions in the Eastern Columbia River Gorge. There may be
some patchy blowing dust in the Lower Columbia Basin and along
the Foothills of the Blue Mountains this afternoon. The cooling
trend and dry conditions will continue on Sunday for highs 81 to 91,
except in the mid 60s to lower 80s in the mountains. A mid upper
level low approaches the coast Monday backing flow aloft to the
SW resulting in high temperatures Monday a few degrees warmer. Polan

LONG TERM...Monday night through Saturday...An upper low pressure
system off the Washington Coast will work its way inland Monday
night and Tuesday. This will result in lowering heights, thicknesses
and 850 MB temperatures which will result in a cooling trend. On
Tuesday maximum temperatures will only be in the lower to mid 80s in
the lower elevations which will be about 6 to 8 degrees below
normal. This system will have very little moisture with it...but
there may be enough for some isolated showers and afternoon
thunderstorms over the central Washington Cascade east slopes Monday
night through Tuesday night. The rest of the CWA will remain dry. It
will also become locally breezy to windy...mainly along the Cascade
east slopes and through the Cascade gaps and passes. As the upper
low pushes east on Tuesday into Wednesday the flow will become west
to northwest again resulting in dry conditions...with a warming
trend through Friday. By Friday afternoon the flow will become
southwest again which will bring up some moisture and instability
from the south. Though moisture will be limited again there may be
enough, with instability, for a few showers and afternoon
thunderstorms over the Wallowa and Elkhorn Mountains Friday
afternoon through Saturday. Elsewhere will be dry and temperatures
will be around normal for the time of year Friday and Saturday. 88


FIRE WEATHER...Red Flag Warnings are in effect through this evening
for gusty winds and low relative humidity for the fire zones
covering the Eastern Columbia River Gorge and the east slopes of the
Northern Oregon Cascades (fire zones WA/OR639 and OR610). Red Flag
Warnings are also in effect from 1 PM to 9 PM today for the Columbia
Basin zones down to Central Oregon (WA675, WA/OR639, and OR640).
Taking a closer look at Sunday...the winds will not be strong enough
to extend the warning for an additional day. Conditions are not
expected to meet red flag criteria elsewhere but there will be local
winds around 10-15 mph along with relative humidity values around 10
to 15 percent that will be a concern, but the potential for extreme
fire behavior will be low.

&&

.PRELIMINARY POINT TEMPS/POPS...
PDT  94  57  87  57 /   0   0   0   0 
ALW  94  63  87  62 /   0   0   0   0 
PSC  97  61  90  59 /   0   0   0   0 
YKM  95  58  90  58 /   0   0   0   0 
HRI  97  60  89  58 /   0   0   0   0 
ELN  88  57  85  56 /   0   0   0   0 
RDM  91  45  88  47 /   0   0   0   0 
LGD  92  51  85  49 /   0   0   0   0 
GCD  94  52  88  52 /   0   0   0   0 
DLS  88  60  86  60 /   0   0   0   0 

&&

.PDT Watches/Warnings/Advisories...
OR...Red Flag Warning until 9 PM PDT this evening for ORZ610-639.

     Red Flag Warning from 1 PM this afternoon to 9 PM PDT this 
     evening for ORZ640-641.

WA...Red Flag Warning until 9 PM PDT this evening for WAZ639.

     Red Flag Warning from 1 PM this afternoon to 9 PM PDT this 
     evening for WAZ641-675.

&&

$$

79/88/93

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