

076 

AGPN40 KWNM 032101

MIMPAC



MARINE WEATHER DISCUSSION FOR N PACIFIC OCEAN

NWS OCEAN PREDICTION CENTER WASHINGTON DC

201 PM PDT WED AUG 3 2016



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

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



THE 18Z OPC SFC ANALYSIS INDICATES THE PRES GRADIENT ALONG THE W

COAST REMAINS PINCHED THIS AFTN BETWEEN A STNRY 1040 MB HIGH PRES

CENTER NEAR 44N147W AND A 1012 MB LOW/THERMAL TROUGH OVER NRN CA.

A RECENT ASCAT PASS FROM 1805Z SHOWS A BROAD AREA OF 20-30 KT NLY

WINDS OVER THE SRN OR/NRN CA WATERS...HIGHEST WITHIN THE E PORTION

OF THE INNER NRN CA OFFSHORE ZONE FROM PT ST GEORGE TO PT ARENA.



THE 12Z GFS/ECMWF RUNS CONTINUE TO INDICATE THE POTENTIAL FOR

GALES OVER THE NE PORTION OF PZ820 BEGINNING AFTER 00Z THU. WHILE 

THE STRONGEST WINDS WILL LIKELY REMAIN OVER THE COASTAL WTRS...

OFFSHORE HIGH PRES WAS ANALYZED SLIGHTLY STRONGER THAN THE MODELS

WERE PREVIOUSLY INDICATING...AND IT IS EXPECTED TO REMAIN STNRY

THRU TONIGHT INTO THU. THEREFORE...CONFIDENCE WAS HIGH ENOUGH TO

MAINTAIN MARGINAL GALES FOR PZ820. FURTHERMORE...BOTH THE 12Z

GFS/ECMWF DEPICT A FAIRLY SHARP INLAND TROUGH OVER NRN CA UNTIL

18Z THU...AND THE MODEL WIND FIELDS HINT AT A SECONDARY SPEED MAX

OVER OUR WTRS AROUND 12Z THU WITH THE STRONG HIGH REMAINING STNRY.

THEREFORE...HAVE EXTENDED THE GALE WARNING FOR PZ820 INTO THU

MORNING WITH THIS ISSUANCE.



AN UPPER LOW CURRENTLY OVER THE ERN GULF OF AK WILL MOVE SE OVER

THE NEXT COUPLE DAYS...NEARING VANCOUVER ISLAND BY FRI MORNING.

THIS FEATURE WILL HELP WEAKEN THE OFFSHORE RIDGE AND RELAX THE

PRES GRADIENT ALONG THE W COAST THROUGH THE WEEKEND. SO AFTER 18Z

THU...DO NOT ANTICIPATE ANY GALES OVER THE OFFSHORE WTRS THRU MON

NIGHT.



THE 12Z GFS WAS THE MODEL OF CHOICE FOR MOST OF THE PERIOD.

STARTED WITH A BLEND OF THE 30M/10M WINDS THRU THU MORNING TO

PRODUCE THE SMALL AREA OF GALES DETAILED ABOVE. THEN USED THE GFS

10M WINDS THRU 18Z SUN. TRANSITIONED TO THE 12Z ECMWF AFTER 18Z

SUN AS THIS SOLUTION GENERATED SLIGHTLY STRONGER WINDS OVER THE

PZ5 WATERS INTO MON...WHICH MATCHED UP BETTER WITH THE 12Z UKMET.



.SEAS...THE 12Z NWW3 WAS USED THRU SUN MORNING WITH A 10 PCT WAVE

HGT BOOST IN THE NEAR TERM TO ACCOUNT FOR THE MODELS RUNNING

SLIGHTLY LOW WITH GALES IN THE FCST. THEN POPULATED WITH THE 12Z

WAM SUN THROUGH MON NIGHT TO REMAIN CONSISTENT WITH THE FCST

WINDS.



.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 TONIGHT INTO THU. 



$$



.FORECASTER REINHART. OCEAN PREDICTION CENTER.

