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737 

AGPN40 KWNM 070228

MIMPAC



MARINE WEATHER DISCUSSION FOR N PACIFIC OCEAN

NWS OCEAN PREDICTION CENTER WASHINGTON DC

728 PM PDT TUE SEP 6 2016



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

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



THE LATEST MODEL GUIDANCE INDICATES THAT HIGH PRES W OF THE NRN

PZ6 WATERS CONTINUES TO COMBINE WITH A LOW PRES TROF OVER

CALIFORNIA TO PRODUCE N TO NW WINDS UP TO 30 KT OR SO OFF THE

COAST OF NRN AND CENTRAL CALIFORNIA WITH THE STRONGEST CONDITIONS

W OF POINT ARENA. MINIMAL GALES ARE LIKELY TONIGHT W OF POINT

ARENA AND POINT REYES. BY LATE WED THE STRONGEST CONDITIONS WILL

SHIFT N TO OFF OF CAPE MENDOCINO WITH MINIMAL GALES AGAIN A

POSSIBILITY. A BETTER CHANCE OF GALES WILL OCCUR BY THU NIGHT W OF

POINT SAINT GEORGE AS THE THERMAL TROF STRENGTHENS OVER NRN

CALIFORNIA. THESE GALE CONDITIONS WILL THEN CONTINUE INTO FRI

BEFORE DIMINISHING SOMEWHAT. CURRENT WARNINGS LOOK REASONABLE AND

FEW CHANGES SHOULD BE NEEDED ON THE NEXT OFFSHORE FORECAST.



THE NWW3 LOOKS REASONABLE WITH THE SEAS AND WILL BE FOLLOWED

FAIRLY CLOSELY DURING THE FORECAST PERIOD.



EXTRATROPICAL STORM SURGE GUIDANCE...N/A.



-----------------------------------------------------------------

PREVIOUS DISCUSSION...



THE MAIN WEATHER CONCERN OVER THE OFFSHORE WATERS FOR THE NEXT

FEW DAYS WILL BE THE THREAT FOR GALES MAINLY OVER EASTERN

SECTIONS OF THE OFFSHORE WATERS FROM CENTRAL CALIF NORTHWARD TO

THE SRN OREGON OFF WTRS. HURRICANE NEWTON WAS NEAR 24.7N 111.4W

OR OVER THE BAJA CALIFORNIA AREA OF NW MEXICO MOVG NW PER THE

11AM PDT INTERMEDIATE ADVISORY FROM THE NATIONAL HURRICANE

CENTER. NEWTON IS FCST TO REMAIN AT LEAST 250 NM SE AND E OF THE

OFFSHORE WTRS THRU TONITE INTO WED...WITH THE SYSTEM DISSIPATING

OVER NRN MEXICO OR THE SW U.S. WED NITE OR EARLY THU. FOR

ADDITIONAL INFORMATION REGARDING NEWTON PLS REFER TO THE LATEST

ADVISORIES FROM NHC.



SHORT TERM...A SHIP NEAR 31.5N 124W AT 18Z REPORTED WINDS NR 34

KT. AFTER A QC AND BUDDY CHECK FROM NEARBY OBS IT APPEARS AS IF

HIS OBSERVATION IS RUNNING AROUND 5 KT TOO HIGH. ALSO THE JUST

ARRIVING ASCAT PASS FROM THE AREA INDICATED ONLY MAX WINDS NR 25

TO 30 KT OCCURRING OVR THIS REGION. OVERALL..FOR THE SHORT TERM

PART OF THE FCST THE ONLY CHANGE TO THE PREV FCST WILL BE TO ADD

A PERIOD OF MARGINAL GALES TO THE OFFSHORE WTRS ADJACENT TO THE

CENTRAL CALIF WTRS (ZONE PZZ825) FOR A TIME TONITE INTO EARLY

WED...AS CHANCES FOR THESE GALES OCCURRING APPEAR TO BE AT LEAST

NEAR AVERAGE. WE WILL ONCE AGAIN RELY ON THE 12Z GFS WINDS FOR

THE AFTN PACKAGE...USING A BLEND OF THE LKLY TOO STRONG 30M WINDS

AND THE LKLY A LITTLE TOO LOW 10M WINDS FOR TONITE INTO EARLY

WED. OTW...WE WILL USE THE 10M WINDS FOR THE AFTN FCST PACKAGE

INTO THU...WITH THE 12Z GLOBAL MODELS REMAINING IN EXCELLENT

AGREEMENT OVR THE OFF WTRS. A FEW MANUAL EDITS WILL BE MADE TO

THE GRIDS TO FIT THE AFTN OPC FCST WITH NEARBY COASTAL AND TAFB

FCSTS.



LONG TERM...WE WILL CONTINUE TO RELY ON THE 12Z GFS FOR LATE THU

THRU SUN NITE OVR THE OFFSHORE WTRS...AS NEARLY ALL 12Z GLOBAL

MDLS REMAIN IN VRY GOOD AGREEMENT OVR THE REGION THRU THE

UPCOMING WKND. TO MAINTAIN CONTINUITY FROM THE PREV FEW FCSTS WE

WILL USE A BLEND OF THE 30M AND 10M WINDS OFF THE SRN OREG AND

NRN CALIF COAST LATER THU AND THU NITE. THIS WILL HELP US

MAINTAIN THE PREV GALE FORCE WINDS FOR NE NOCAL AND FAR SE OREG

OFF WTRS FOR THU NITE...WITH A FEW MANUAL EDITS AS WELL. OTW...WE

WILL CONT TO USE THE GFS 10M WINDS FOR THE OFF WTRS FCST THRU SUN

NITE. MARGINAL GALES APPEAR PSBL AGAIN SUN NITE OVR ERN NOCAL OFF

WTRS AS THE PRES GRADIENT TIGHTENS BETWEEN HIGH PRES BUILDING NW

OF THE WTRS AND LOWER PRESSURES OVR THE ROCKIES. CONFDC LVLS IN

THE GALES THU NITE AND AGAIN SUN NITE ARE NEAR AVERAGE AT THIS

TIME.



SEAS...BOTH THE 12Z ENP WAVE WATCH III AND 12Z ECMWF WAM WAVE

MODELS APPEAR TO HAVE INTIALIZED WELL OVR THE REGION PER THE

LATEST OBS. WE WILL STAY CLOSE TO THE 12Z ENP WW3 MDL FOR THE AFTN

PACKAGE...EXCEPT TO MAKE A FEW MANUAL ADJUSTMENTS TO FIT INITIAL

CONDITIONS...AND NEARBY COASTAL AND TAFB GRIDS AND FCSTS.

INITIALLY IT APPEARS AS IF WE MAY NEED TO ADD A FT OR TWO TO THE

WW3 MDL GUID OFF THE CENTRAL CALIF COAST.



EXTRATROPICAL STORM SURGE GUIDANCE...N/A.





.WARNINGS...PRELIMINARY.



.PZ5 WASHINGTON/OREGON WATERS...

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

     GALE POSSIBLE THU NIGHT.



.PZ6 CALIFORNIA WATERS...

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

     GALE POSSIBLE THU NIGHT.

     GALE POSSIBLE SUN NIGHT.

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

     GALE TONIGHT INTO WED. 



$$



.FORECASTER NOLT/MILLS. OCEAN PREDICTION CENTER.

