

808 

AGPN40 KWNM 142051

MIMPAC



MARINE WEATHER DISCUSSION FOR N PACIFIC OCEAN

NWS OCEAN PREDICTION CENTER WASHINGTON DC

151 PM PDT SUN AUG 14 2016



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

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



A NEW 1026 MB HIGH PRES CENTER HAS DEVELOPED NEAR 40N138W THIS

AFTN ACCORDING TO THE 18Z NCEP SFC ANALYSIS. AN INLAND TROUGH

PERSISTS OVER NRN/CENTRAL CA WITH SEASONAL NLY WINDS ACROSS THE

OFFSHORE WTRS. A 1740Z ASCAT-B PASS REVEALED 10-20 KT NLY WINDS

OVER THE CENTRAL PZ6 WTRS...MATCHING UP WELL WITH THE CURRENT FCST

GRIDS.



THE 12Z GLOBAL MODELS REMAIN IN GOOD AGREEMENT REGARDING THE

SYNOPTIC PATTERN OVER THE NEXT SEVERAL DAYS. SFC HIGH PRES WILL

REMAIN NEARLY STNRY THRU TONIGHT...THEN STRENGTHEN MON THRU THU AS

THE RIDGE AXIS EXPANDS NWD ALONG 140W. THIS WILL PRODUCE A PINCHED

PRES GRADIENT ALONG THE W COAST...RESULTING IN STRENGTHENING WINDS

MAINLY OVER THE SRN PZ5/NRN PZ6 WTRS THRU MID WEEK. THE 12Z GFS

KEEPS GALES CONFINED TO THE COASTAL WTRS ON MON...BUT A SHARPENING

INLAND TROF OVER CA COMBINED WITH HIGH PRES OFFSHORE SHOULD ALLOW

GALES TO EXPAND INTO OUR OFFSHORE WTRS BEGINNING TUE NIGHT AND

CONTINUING THRU EARLY THU. USED A BLEND OF THE 12Z GFS 10M/30M

WINDS DURING THIS PERIOD TO ACCOUNT FOR THE 10M WINDS POSSIBLY

BEING UNDERDONE WITHIN THIS ENHANCED GRADIENT. GALE CONFIDENCE IS

HIGHEST FOR PZZ820 AS BOTH THE 12Z GFS/UKMET DEPICT GALES IN THIS

ZONE...WHILE THE THREAT FOR THE SE PORTION OF PZZ815 IS MORE

MARGINAL ATTM.



A SECOND AREA OF INTEREST EMERGES TUE NIGHT INTO WED AS A SFC TROF

DEVELOPS NEAR THE WA COAST AND EXTENDS ACROSS VANCOUVER ISLAND.

THE NRN PZ5 WTRS CAN EXPECT STRENGTHENING WINDS ON WED BTWN THIS

TROF AND THE STRONG RIDGE OFFSHORE. THE 12Z GFS HAS BACKED OFF THE 

GALES A BIT COMPARED TO PREVIOUS RUNS. HOWEVER...WITH ENV CANADA

AND OUR PREVIOUS FCST BOTH CARRYING GALES...WILL MAINTAIN A SMALL

POCKET OF GALES OVER THE EXTREME NRN PORTION OF PZZ800 ON WED.

SFC HIGH PRES MOVES NW AWAY FROM THE WTRS THU AND FRI...AND ALL

THE MODELS DEPICT A WEAK SFC LOW DVLPG OVER THE CENTRAL PZ6 WTRS

BY FRI. THIS RESULTS IN THE STRONGEST NLY FLOW SHIFTING WELL

OFFSHORE AS THE SFC RIDGE RECEDES W OF THE WTRS.



THE 12Z GFS WAS THE PREFERRED MODEL TODAY...ALTHOUGH AS MENTIONED

ABOVE THE GUIDANCE WAS IN VERY GOOD AGREEMENT OVERALL. STUCK WITH

THE 10M WINDS THRU MOST OF THE PERIOD...EXCEPT USED A 10M/30M

BLEND TO BEST DEPICT THE EXPECTED GALES TUE THRU WED NIGHT.



.SEAS...THE 12Z NWW3 INITIALIZED WELL AND GENERATED SLIGHTLY

HIGHER SEAS THRU TONIGHT...SO IT WAS THE PREFERRED STARTING

POINT FOR THE WAVE GRIDS. IN FACT...THE NWW3 WAS USED FOR MOST OF

THE PERIOD AS OVERALL IT WAS FAIRLY CONSISTENT WITH THE 12Z ECMWF

WAM. HOWEVER...DID PREFER THE WAM SEAS FROM 00Z-12Z WED AS THE

NWW3 BUILT SEAS TOO SLOWLY WITH THE FCST GALES. HIGHEST SEAS ARE

EXPECTED ON WED PEAKING AROUND 15-16 FT OFF THE NRN CA COAST.





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





.WARNINGS...PRELIMINARY.



.PZ5 WASHINGTON/OREGON WATERS...

.PZZ800...INNER WATERS FROM CAPE FLATTERY TO CAPE SHOALWATER...

     GALE POSSIBLE WED INTO WED NIGHT. 

.PZZ815...INNER WATERS FROM FLORENCE OR TO POINT ST. GEORGE...

     GALE POSSIBLE TUE NIGHT INTO WED NIGHT. 



.PZ6 CALIFORNIA WATERS...

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

     GALE POSSIBLE TUE NIGHT INTO WED NIGHT. 



$$



.FORECASTER REINHART. OCEAN PREDICTION CENTER.

