

566 

AGPN40 KWNM 051501

MIMPAC



MARINE WEATHER DISCUSSION FOR N PACIFIC OCEAN

NWS OCEAN PREDICTION CENTER WASHINGTON DC

801 AM PDT FRI AUG 5 2016



.FORECAST DISCUSSION: MAJOR FEATURES/WINDS/SEAS/SIGNIFICANT

.WEATHER FOR THE NORTH PACIFIC N OF 30N AND E OF 150W.



STNRY 1035 MB HIGH PRES IS LOCATED NEAR 45N147W THIS MORNING PER

THE 12Z NCEP SFC ANALYSIS. A SFC TROF EXTENDS NWD ALONG THE COAST

OF BRITISH COLUMBIA FROM A 1011 MB LOW ANALYZED NEAR VANCOUVER. N

TO NW WINDS 20-25 KT PREVAIL ACROSS THE PZ5/NRN PZ6 WTRS BETWEEN

THESE FEATURES...AS INDICATED BY RECENT SFC OBS AND EARLIER HIGH

RES ASCAT AND RSCAT PASSES. THIS MATCHES UP WELL WITH OUR CURRENT

FCST GRIDS...SO NO SIGNIFICANT CHANGES ARE NECESSARY WITH THIS

MORNING UPDATE. WILL POPULATE WITH GFS 10M WINDS IN THE NEAR TERM

AS THESE APPEAR TO BE MOST REPRESENTATIVE ATTM.



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PREVIOUS DISCUSSION...



A HIGH RES ASCAT-A PASS WITH GOOD COVERAGE RETURNED A SWATH OF

MOSTLY N TO NW 20 TO 25 KT ACRS MUCH OF THE AREA W OF 120W WITH A

SMALL AREA OF HIGHER WINDS 30 KT W OF VANCOUVER ISL AND EXTENDING

INTO PZZ800...AND NO GALES DETECTED IN OFSHR AND CSTL WTRS. THE

HIGHER WINDS ARE DUE TO CHANNELING BETWEEN THE STRONG HIGH PRES

RDG TO THE W AND A SFC TROF WHICH HAS FORMED NR VANCOUVER ISL. IR

AND W/V STLT LOOPS SHOW A MID/UPR LOW APCHG VANCOUVER ISL FM THE N

AND AHEAD OF IT INDICATIONS OF A WK FNTL BNDRY ENTERING THE WA

WTRS...IN FACT WPC FAS A FCST WK CDFNT IN WA WTRS IN 12 HR FCST

VALID 12Z FRI. FOR THE NEAR TERM USED A BLEND OF 00Z GFS 10M AND

30M WINDS WEIGHTED 66 PCT IN FAVOR OF 10M WINDS...WHICH LOOKS

REPRESENTATIVE.



OTRW A TYPICAL SUMMER PATTERN WILL CONTINUE OVER THE E PAC THRU

THE FCST PERIOD...WITH THE OVERALL TREND CALLING FOR THE PRES

GRADIENT ALONG THE W COAST TO GRADUALLY RELAX OVER THE NEXT

FEW DAYS AS THE UPR LOW NEAR VANCOUVER ISLAND TODAY CONTINUES

DRIFTING S THRU SUN. 00Z GLOBAL MODELS SHOW WEAKENING HIGH PRES

OFFSHORE AND WEAKENING WINDS THRU THE WEEKEND...GENERALLY

BECOMING 15-20 KT OVER THE PZ6 AND SRN PZ5 WTRS BY SUN. THIS UPR

LOW IS FCST BY MDLS TO TURN INLAND ACROSS WA SUN NIGHT INTO

MON...ALLOWING THE OFFSHORE UPR AND SFC RIDGES TO RESTRENGTHEN

THRU THE END OF THE FCST PERIOD. BY 12Z TUE...THE 00Z GFS/ECMWF

AS WELL AS THE UKMET/GEM SHOW INCREASED AGRMT SUPPORTING GALE

CONDS REDVLPG OFF THE NRN CA COAST POSSIBLY EXTENDING FM CSTL

WTRS...WHERE THEY ARE MOST LKLY...INTO ADJ OFSHR ZONES PZZ820 AND

825. ALSO NOTE IN 00Z ECMWF APPEARANCE OF A NLY SURGE ASCD WITH

BLDG RDG OFSHR RESULTING IN LOWERING STATIC STABILITIES EXTENDING

S INTO CA WTRS. THEREFORE FOR THIS REASON AND WITH BETTER MDL SPRT

EVEN WITH 10M WINDS...WILL POST GALES FOR MON NIGHT INTO TUE ASCD

WITH THIS SURGE WITH MDT CONFDC...USING A 50/50 BLEND OF 00Z GFS

10M AND 30M WINDS. OTRW DURING THE REMAINDER OF THE FCST PERIOD FM

FRI NIGHT ON...USED MOSTLY REPRESENTATIVE GFS 10M WINDS OUTSIDE OF

THE PERIOD OF GALES.



.SEAS...USED THE 00Z ECMWF WAM INITIALLY FOR FIRST PERIOD WITH

MINOR ADJUSTMENTS MATCHING UP WITH ADJ CSTL WTRS AND THEN AFTER

TODAY POPULATED WAVE GRIDS WITH 00Z ENP NWW3 WITH MDLS SHOWING

ONLY MINOR DIFFERENCES.



.EXTRATROPICAL STORM SURGE GUIDANCE...N/A.





.WARNINGS...PRELIMINARY.



.PZ5 WASHINGTON/OREGON WATERS...

     NONE.



.PZ6 CALIFORNIA WATERS...

.PZZ820...INNER WATERS FROM POINT ST. GEORGE TO POINT ARENA...

     GALE POSSIBLE MON NIGHT INTO TUE. 

.PZZ825...INNER WATERS FROM POINT ARENA TO PIGEON POINT...

     GALE POSSIBLE MON NIGHT INTO TUE. 



$$



.FORECASTER REINHART/BANCROFT. OCEAN PREDICTION CENTER.

