Area Forecast Discussion
Issued by NWS Portland, OR

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FXUS66 KPQR 082237
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND OR
236 PM PST MON FEB  8 2016

.SYNOPSIS...A STRONG UPPER RIDGE WILL BE OVER THE PACIFIC NORTHWEST
TONIGHT AND TUESDAY WITH BRISK OFFSHORE FLOW THROUGH THE COLUMBIA
RIVER GORGE. THE UPPER RIDGE WILL WEAKEN AND MOVE EAST LATER TUESDAY
AND WEDNESDAY AS THE FIRST WEAK SYSTEM REACHES THE COAST WEDNESDAY.
OTHER SYSTEMS WILL TRY TO MAKE INROADS INTO THE PACIFIC NORTHWEST THE
REMAINDER OF THE WEEK AND ESPECIALLY NEXT WEEKEND.
&&

.SHORT TERM...TONIGHT THROUGH THURSDAY...A STRONG UPPER RIDGE IS IN
PLACE OVER THE PACIFIC NORTHWEST THIS AFTERNOON...AND THIS PATTERN
WILL NOT CHANGE MUCH UNTIL LATER TUESDAY. THIS IS RESULTING IN BRISK
OFFSHORE FLOW THROUGH THE GORGE AS SURFACE PRESSURE GRADIENTS HAVE
ALREADY REACHED OVER 8 MB FROM THE DALLES TO TROUTDALE...SUPPORTING
GUSTS 50 TO 60 MPH AT ROOSTER ROCK AND CORBETT AND 70 MPH OR HIGHER
AT CROWN POINT. THE WINDS ARE LESS ELSEWHERE AS THERE IS NOT MUCH
SUPPORT AT 850 MB OR 700 MB...BUT THERE IS A BIT OF A BREEZE ALONG
THE COAST AND OVER THE HIGHER TERRAIN. THE LAST VESTIGES OF LOW
CLOUDS IN THE SOUTHERN WILLAMETTE VALLEY HAVE CLEARED THIS
AFTERNOON...THOUGH SOME HAVE FORMED IN HOOD RIVER COUNTY EARLIER
TODAY IN THE UPSLOPE OFFSHORE FLOW THAT WILL CONTINUE FOR THE NEXT
COUPLE OF DAYS.

WEATHER WISE...NOT MUCH CHANGE TONIGHT AND TUESDAY. EXPECT ANOTHER
MILD OR WARM DAY OVER MUCH OF THE AREA TUESDAY. WIND SHELTERED AREAS
OR AREAS THAT DECOUPLE FROM ANY WIND WILL GET COOL TONIGHT...INTO THE
30S...DUE TO GOOD RADIATIONAL CONDITIONS IN THE DRIER AIR MASS OVER
THE AREA. LOOK FOR MORE AREAS OF FOG AND LOW CLOUDS INLAND AWAY FROM
THE GORGE...BUT DO NOT EXPECT MORE COVERAGE THAN WHAT WE SAW THIS
MORNING...AND PROBABLY NO LATER CLEARING EITHER.

THE UPPER RIDGE STARTS TO MOVE OFF TO THE EAST LATER TUESDAY DUE TO
THE GRADUAL APPROACH OF THE NEXT SYSTEM...AND THE EAST WINDS SHOULD
START TO EASE ESPECIALLY TUESDAY NIGHT AND WEDNESDAY. THE NEXT SYSTEM
WILL TURN THE WINDS MORE SOUTHERLY ALONG THE COAST TUESDAY NIGHT AND
WEDNESDAY...AND WE SHOULD SEE LOW CLOUDS DEVELOP THERE. THE WEAK
SYSTEM REACHES THE COAST WEDNESDAY BUT DOES NOT REALLY MAKE MUCH
HEADWAY INLAND AS IT LIFTS OUT TO THE NORTH. WILL HAVE SOME LOW POPS
ON THE COAST WEDNESDAY BUT THAT IS ABOUT IT. WITH THE WEAKER OFFSHORE
FLOW...THE FOG AND LOW CLOUDS INLAND SHOULD INCREASE IN COVERAGE
TUESDAY NIGHT AND WEDNESDAY MORNING BEFORE BREAKING UP WEDNESDAY
AFTERNOON.

THURSDAY WILL CONTINUE TO SEE THE SOUTHWEST FLOW ALOFT THAT HAD
DEVELOPED WEDNESDAY WITH THE UPPER RIDGE AXIS OVER IDAHO AND A LOW
OUT AROUND 140W TO 150W...BUT THE MAIN CHANCE OF ANY PRECIPITATION
LOOKS TO BE THE NORTH COASTAL AREAS AS MUCH OF THE ENERGY HEADS
FARTHER NORTH INTO WESTERN WASHINGTON. TOLLESON

.LONG TERM...THURSDAY NIGHT THROUGH MONDAY...THE MODELS ARE
INDICATING WE WILL STAY UNDER SOUTHWEST FLOW ALOFT EARLY IN THE
PERIOD...THEN HAVE A FRONT COME THROUGH LATE FRIDAY INTO SATURDAY...
WITH THE GFS THE SLOWEST AND THE ECMWF THE FASTEST. THE MODELS
SUGGEST WE GET BACK INTO WEST TO SOUTHWEST FLOW FOLLOWING THAT
SYSTEM...WITH THE GFS CONSIDERABLY DRIER THAN THE ECMWF OR GEM
MODELS. HAVE TRENDED TOWARD CLIMO POPS FOR SUNDAY AND MONDAY.
TOLLESON
&&

.AVIATION...OFFSHORE FLOW MEANS VFR CONDITIONS FOR THE NEXT 24 HRS AT
COASTAL SITES. FOG WILL REDEVELOP LATE THIS EVENING IN THE SOUTH AND
CENTRAL WILLAMETTE VALLEY AS NORTHERLY WINDS DROP OFF. THIS WILL
LOWER CIGS AND VIS TO LIFR AT KEUG...BUT KSLE MAY DRIFT IN AND OUT OF
IT SIMILAR TO LAST NIGHT. WILL PROBABLY ALSO SEE FOG AT KHIO DEVELOP
AFTER MIDNIGHT. EASTERLY WINDS THROUGH THE GORGE WILL KEEP KTTD AND
KPDX VFR THROUGH TUESDAY MORNING.

KPDX AND APPROACHES...VFR CONDITIONS FOR THE NEXT 24 HRS. EASTERLY
WINDS INCREASING NEAR THE GORGE THIS AFTERNOON WITH GUSTS UP TO 50 KT
POSSIBLE NEAR THE WEST END OF THE GORGE. WINDS DECREASING AFTER 09Z
TUESDAY. -MCCOY
&&

.MARINE...OFFSHORE WINDS STAY FAIRLY BENIGN TODAY...EXCEPT GUSTS UP
TO 20 KT NEAR GAPS IN THE COASTAL TERRAIN. WINDS THROUGH THESE GAPS
DECREASE AFTER MIDNIGHT TONIGHT. NEXT SYSTEM APPROACHES ON TUESDAY
STARTING OFF ANOTHER ROUND OF ACTIVE WEATHER THROUGH THE WEEKEND. THE
WARM FRONT AHEAD OF THIS SYSTEM WILL SHIFT WINDS TO SOUTHERLY ACROSS
THE WATERS ON TUESDAY. WINDS FOR THE MOST PART SHOULD STAY BELOW 20
KT...BUT WE MAY SEE A FEW GUSTS ABOVE 20 KT IN THE FAR OUTER WATERS.
NOT CONFIDENT RIGHT NOW THESE GUSTS ABOVE 20 KT WILL BE FREQUENT
ENOUGH TO WARRANT A SMALL CRAFT ADVISORY. THERE WILL BE A BETTER
CHANCE FOR WINDS T0 INCREASE TO 20 TO 25 KT WITH THE WEAK COLD FRONT
WHICH MOVES THROUGH MIDDAY WEDNESDAY.

SEAS AROUND 10 TO 12 FT THIS AFTERNOON WILL DROP BACK DOWN TO 7 TO 8
FT TONIGHT THROUGH TUESDAY. WILL SEE SEAS BUILD BACK UP TO AROUND 9
FT WITH THE WEAK FRONT MOVING THROUGH ON WEDNESDAY. ANOTHER SYSTEM ON
FRIDAY COULD BRING ANOTHER ROUND OF WINDS GUSTING TO 20 TO 25
KT...AND WILL BUILD SEAS UP INTO THE LOWER TEENS. ACTIVE PATTERN WILL
KEEP SEAS UP ABOVE 10 FT THROUGH THE WEEKEND. -MCCOY
&&

.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 9 PM PST
     THIS EVENING FOR COASTAL WATERS FROM CAPE SHOALWATER WA TO
     FLORENCE OR OUT 60 NM.

     SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR UNTIL
     9 PM PST THIS EVENING.

&&

$$

INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/NWSPORTLAND
WWW.TWITTER.COM/NWSPORTLAND


THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON
FROM THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS
COMMONLY REFERRED TO AS THE FORECAST AREA.



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