Area Forecast Discussion
Issued by NWS Portland, OR

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FXUS66 KPQR 292148
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND OR
248 PM PDT SAT AUG 29 2015

.SYNOPSIS...THE STRONG LOW THAT BROUGHT HIGH WINDS TO THE COAST AND
WINDY CONDITIONS INLAND TODAY HAS MOVED NORTH OF THE AREA WITH SLOWLY
SUBSIDING WINDS. THE NEXT COLD FRONT WAS APPROACHING THE SOUTH
WASHINGTON AND NORTH OREGON COAST THIS AFTERNOON AND WILL MOVE ACROSS
SOUTHWEST WASHINGTON AND NORTHWEST OREGON TONIGHT WITH MORE RAIN AND
MORE BREEZY CONDITIONS ESPECIALLY AT THE COAST. THERE WILL EVEN BE A
SLIGHT CHANCE OF THUNDER THIS EVENING MAINLY NEAR THE COAST. ONSHORE
FLOW BEHIND THE FRONT WILL KEEP A FAIR AMOUNT OF SHOWERS OVER THE
AREA ON SUNDAY. A TROUGH WILL REMAIN NEAR THE COAST THROUGH THE
COMING WEEK...KEEPING THINGS COOL AND SHOWERY AT TIMES.
&&

.SHORT TERM...THE STRONG LOW THAT PRODUCED HIGH WINDS ALONG THE COAST
AND IN THE COAST RANGE TODAY AND WINDY CONDITIONS INLAND HAS NOW
MOVED WELL NORTH INTO NORTHWEST WASHINGTON AND SOUTHERN B.C.  WINDS
IN OUR AREA ARE TAPERING OFF FROM SOUTH TO NORTH AND HAVE BEEN
DROPPING THE WARNINGS AND ADVISORIES AS APPROPRIATE THIS AFTERNOON. A
PUBLIC INFORMATION STATEMENT WAS ISSUED EARLIER THIS AFTERNOON WITH
PEAK WIND VALUES ACROSS THE AREA...AND THEY WERE PRETTY IMPRESSIVE.
THERE ARE STILL SOME SHOWERS OVER THE COAST RANGE IN SOUTHWEST FLOW
THAT WILL AFFECT THE NORTHERN ZONES AT TIME THIS BUT LESS IN THE
SOUTHERN ZONES. WITH TEMPS IN THE LOWER 70S THERE IS A SMALL CHANCE
OF THUNDER THIS AFTERNOON AS WELL.

ATTENTION NOW TURNS TO THE NEXT FRONT...CURRENTLY APPROACHING THE
SOUTH WASHINGTON AND NORTH OREGON COAST. THE NORTH PART OF THIS FRONT
IS MERGING WITH THE BENT BACK OCCLUSION OF THE STRONG LOW THAT MOVED
NORTH EARLIER TODAY. THERE IS A LIGHTNING STRIKE ALONG THIS FRONT
THIS AFTERNOON AS WELL...WEST OF ASTORIA. THIS FRONT WILL REACH THE
COAST THIS AFTERNOON AND EARLY EVENING AND SPREAD THROUGH SOUTHWEST
WASHINGTON AND NORTHWEST OREGON OVERNIGHT TONIGHT. AS INDICATED
ABOVE...THIS FRONT IS SOMEWHAT CONVECTIVE IN NATURE...AND THERE WILL
BE A SLIGHT CHANCE OF THUNDER WITH IT ALONG THE COAST AND IN THE
NORTH INTERIOR ZONES AGAIN. THERE IS SOME WIND WITH IT... ESPECIALLY
NEAR THE COAST...BUT NOT AS WINDY AS TODAY. LOOK FOR GUSTS TO AROUND
40 MPH AT THE NORMALLY WINDIER EXPOSED LOCATIONS ALONG THE COAST THIS
EVENING.

ONSHORE FLOW WILL CONTINUE BEHIND THE FRONT ON SUNDAY FOR DECENT
SHOWER COVERAGE THROUGH THE DAY...ESPECIALLY OVER THE MOUNTAINS.

MONDAY WILL CONTINUE TO SEE ONSHORE FLOW WITH A MIXTURE OF CLOUDS AND
SUNSHINE AND BELOW NORMAL TEMPERATURES. THE MAIN THREAT OF SHOWERS ON
MONDAY WILL BE IN THE NORTH AND NEAR THE HIGHER TERRAIN.

ON TUESDAY THE MODELS AGREE ANOTHER FRONTAL BOUNDARY WILL DROP IN
FROM THE NORTH AND INCREASE THE CHANCE OF RAIN AGAIN. TOLLESON

.LONG TERM...TUESDAY NIGHT THROUGH SATURDAY...AN UPPER TROUGH WILL
REMAIN ALONG THE PACIFIC NORTHWEST COAST THROUGH MUCH OF THE EXTENDED
PERIOD. THE MODELS SHOW ANOTHER DECENT PIECE OF ENERGY SWINGING
THROUGH AROUND WEDNESDAY OR THURSDAY FOR A BETTER CHANCE OF
SHOWERS...BUT THE TIMING VARIES A BIT. THE MODELS ARE INDICATING IT
MAY DRY OUT AND START TO WARM UP SOME NEXT WEEKEND. TOLLESON
&&

.AVIATION...MIX OF VFR AND MVFR ALONG THE COAST...MOSTLY VFR INLAND.
GUSTY SOUTHERLY WINDS ARE STARTING TO WEAKEN ACROSS THE AREA. A WEAK
FRONT APPROACHING THE COAST WILL BRING MVFR CIGS TO THE COAST FOR THE
OVERNIGHT HOURS THROUGH SUNDAY MORNING. MODELS SUGGEST MVFR CIGS MAY
CONTINUE INTO THE AFTERNOON HOURS. SOUTHERLY WINDS WILL CONTINUE TO
GUST TO 25 KT AT COASTAL TAF SITES OVERNIGHT UNTIL EARLY SUNDAY
MORNING WHEN WINDS DROP TO 10 TO 15 KT. INLAND...VFR CIGS MAY DROP TO
MVFR WITH RAIN AS THE FRONT MOVES THROUGH THIS EVENING... IMPROVING
BACK TO VFR BEHIND THE FRONT FOR THE OVERNIGHT HOURS THROUGH SUNDAY
MORNING. THERE IS A SLIGHT CHANCE OF A THUNDERSTORM WITH THIS FRONT
MAINLY IN THE NORTHERN WILLAMETTE VALLEY. SOUTHERLY WINDS MAY
INCREASE AGAIN JUST AHEAD OF THE FRONT TO 20 TO 25 KT THEN WILL DROP
TO AROUND 10 KT FOR THE OVERNIGHT HOURS THROUGH SUNDAY MORNING.

KPDX AND APPROACHES...VFR CONDITIONS THIS AFTERNOON. S WINDS
DECREASING THIS AFTERNOON AND EVENING MAY BRIEFLY INCREASE BACK UP TO
20 TO 25 KT JUST AHEAD OF FRONT MOVING THROUGH THIS EVENING. FRONT
WILL BRING RAIN WHICH MAY LOWER CIGS TO MVFR. BEHIND THE FRONT...CIGS
SHOULD IMPROVE BACK TO VFR FOR THE OVERNIGHT HOURS AND REMAIN VFR
THROUGH SUNDAY MORNING. -MCCOY
&&

.MARINE...ANOTHER WEAK FRONT IS STARTING TO MOVE THROUGH THE WATERS
THIS AFTERNOON. THERE IS A CHANCE FOR AN ISOLATED THUNDERSTORM AS
THIS FRONT MOVES THROUGH THE WATERS THIS AFTERNOON. SSW WINDS AROUND
20 TO 30 KT GUSTING TO 40 KT THIS AFTERNOON WILL DECREASE TO 15 TO 20
KT GUSTING TO 25 KT BEHIND THE FRONTAL BOUNDARY...BUT WILL CONTINUE
TO BE FROM THE SSW OVERNIGHT TONIGHT. SEAS CURRENTLY UP AT 15 TO 18
FT WILL LOWER THROUGH THE EVENING TO 10 TO 12 FT LATE TONIGHT. WINDS
MAY CONTINUE TO GUST TO 20 TO 25 KT THROUGH SUNDAY MORNING UNTIL THEY
DROP BELOW 20 KT AROUND MIDDAY. SEAS WILL DROP TO AROUND 8 TO 9 FT BY
SUNDAY MORNING AS WELL.

SWELL BEING GENERATED FROM THE UPPER-LEVEL TROUGH SITTING OVER THE
GULF OF ALASKA WILL KEEP SEAS UP AROUND 7 TO 9 FT THROUGH MID-WEEK.
WINDS REMAIN SSW-ERLY UNTIL TUESDAY OR WEDNESDAY WHEN ANOTHER FRONT
WILL MOVE THROUGH THE WATERS...VEERING WINDS BACK TO THE
WEST-NORTHWEST. -MCCOY
&&

.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.

WA...NONE.

PZ...GALE WARNING UNTIL 8 PM PDT 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 AM PDT SUNDAY.

&&

$$

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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