Area Forecast Discussion
Issued by NWS Portland, OR

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FXUS66 KPQR 052140 RRA
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND OR
229 PM PDT THU MAY 5 2016

.SYNOPSIS...SHOWERS AND THUNDERSTORMS WILL CONTINUE OVER THE CASCADES
THIS AFTERNOON AND EVENING AND AGAIN ON FRIDAY CONFINED TO THE LINN
COUNTY CASCADES. ELSEWHERE...HIGH PRESSURE BUILDING OVER THE REGION
WILL BRING A RETURN TO WELL ABOVE AVERAGE TEMPERATURES FOR THE FIRST
HALF OF THE WEEKEND. A WEAK FRONT WILL LIKELY INCREASE MARINE CLOUDS
AND COOL TEMPERATURES CLOSER TO SEASONAL NORMS FOR SUNDAY AND
MONDAY.

&&

.SHORT TERM...STRATUS DECK CLEARED OUT EARLY THIS
AFTERNOON...ALTHOUGH CIRRUS BLOWOFF FROM SOUTHERN OREGON CONVECTION
HAS MOVED OVER THE AREA AND KEPT AT LEAST FILTERED SUN FOR AREAS EAST
OF THE COASTAL RANGE. SHOWERS FORMING ALONG THE CASCADES WILL BECOME
MORE NUMEROUS IN COVERAGE THROUGH THE AFTERNOON WITH A FEW
THUNDERSTORMS LIKELY. GIVEN VERY WEAK STEERING FLOW...EXPECT MAJORITY
OF THE SHOWERS AND THUNDERSTORMS TO REMAIN CONFINED TO THE CASCADES
WITH A FEW DRIFTING INTO THE FOOTHILLS.

GRADUAL CLEARING WILL CONTINUE FROM NORTHWEST TO SOUTHEAST ACROSS THE
FORECAST AREA THROUGH THE NEXT 24 HOURS AS THE UPPER LOW OFF THE
CALIFORNIA COAST SLOWLY DRIFTS EAST. KEPT SLIGHT CHANCE THUNDER
MENTION FOR THE LINN COUNTY CASCADES ON FRIDAY AFTERNOON AND EVENING
AS A FEW STORMS MAY SNEAK INTO OUR FORECAST AREA FROM THE SOUTH.
OTHERWISE...FAIR...WARM WEATHER WILL DOMINATE THE REST OF THE
FORECAST AREA AS HIGH PRESSURE BUILDS IN FOR THE WEEKEND.  BENTLEY

&&

.LONG TERM...AS THE SYSTEM CURRENTLY LOCATED AT 50N AND 160W LIFTS
NORTHEASTWARD AND WEAKENS...IT WILL SEND A WEAK FRONT TOWARDS THE
PACIFIC COAST SATURDAY NIGHT AND INTO SUNDAY MORNING. THIS WILL USHER
IN A FAIRLY STRONG MARINE PUSH WITH SOME DRIZZLE EXPECTED SUNDAY
MORNING. THIS MARINE PUSH WILL ALSO COOL TEMPERATURES BACK TO NEAR
NORMAL SUNDAY AND MONDAY AFTER TEMPERATURES SOAR OVER 15 DEGREES
ABOVE NORMAL ON FRIDAY AND SATURDAY. OFFSHORE FLOW TAKES OVER AGAIN
BY NEXT TUESDAY WHICH WILL LEAD TO AN EXTENDED PERIOD OF WELL ABOVE
NORMAL TEMPERATURES AND LITTLE PRECIPITATION NEXT WEEK.  BENTLEY

&&

.AVIATION...PRIMARILY VFR CONDITIONS AROUND THE AREA THIS
AFTERNOON. THE EXCEPTION IS THE FAR SOUTHERN WILLAMETTE VALLEY
WHERE SOME STUBBORN HIGH END MVFR CONDITIONS PERSIST...WHICH
SHOULD LIFT TO VFR LATE THIS AFTERNOON. LOW CLOUDS MAY RETURN TO
THE CENTRAL COAST AFTER 04Z THIS EVENING...BUT CONFIDENCE NOT
HIGH IN THAT SCENARIO AS MODELS NOW INDICATE HIGHEST BOUNDARY
LAYER MOISTURE REMAINS ON THE SW OREGON COAST.

KPDX AND APPROACHES...VFR CONDITIONS TONIGHT AND FRIDAY.

&&

.MARINE...NOT MUCH CHANGE IN THE OVERALL MARINE PATTERN FOR THE
NEXT COUPLE OF DAYS. WILL MAINTAIN LOW END SMALL CRAFT ADVISORY
OVER THE OUTER WATERS TONIGHT AND INNER WATERS TIL 11PM. WINDS
WILL DECREASE ON FRIDAY TO THE 15-20 KT RANGE...THEN INCREASE TO
AROUND 20-25 KT FRIDAY EVENING...MAINLY OVER THE OUTER WATERS. AN
UPPER LEVEL TROUGH WILL APPROACH THE WATERS FROM THE NW SAT NIGHT
AND SUN. THIS TROUGH WILL INDUCE A FAIRLY STRONG MARINE SURGE WITH
15 TO 25 KT NW WINDS.

THE GENERAL SEA STATE CONTINUES TO BE DOMINATED BY A LARGE WIND-
WAVE COMPONENT. SHORT PERIODS FROM THE FRESH SWELL ARE LEADING TO
CHOPPY SEAS THAT WILL PERSIST THROUGH THE EVENING HOURS. TW

&&

.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...SMALL CRAFT ADVISORY FOR WINDS UNTIL 5 AM PDT FRIDAY FOR WATERS
     FROM CAPE SHOALWATER WA TO FLORENCE OR FROM 10 TO 60 NM.

     SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 11 PM PDT THIS
     EVENING FOR COASTAL WATERS FROM CAPE SHOALWATER WA TO
     FLORENCE OR OUT 60 NM.

     SMALL CRAFT ADVISORY FOR WINDS UNTIL 11 PM PDT THIS EVENING FOR
     COASTAL WATERS FROM CAPE SHOALWATER WA TO CASCADE HEAD OR
     OUT 10 NM.

     SMALL CRAFT ADVISORY FOR WINDS UNTIL 1 AM PDT FRIDAY FOR
     COASTAL WATERS FROM CASCADE HEAD TO FLORENCE OR OUT 10 NM.

     SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR UNTIL 6 PM
     PDT THIS EVENING.

     SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR FROM 3 AM TO
     7 AM PDT FRIDAY.

&&

$$

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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