

195 

AGPN40 KWNM 061445

MIMPAC



MARINE WEATHER DISCUSSION FOR N PACIFIC OCEAN

NWS OCEAN PREDICTION CENTER WASHINGTON DC

745 AM PDT TUE SEP 6 2016



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

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



NO MAJOR CHANGES APPEAR NEEDED TO THE PREVIOUS FCST FOR THE

MID-MORNING UPDATE. THE 06Z GFS IS VRY SIMILAR TO THE 00Z CYCLE

WHICH WAS USED TO POPULATE GRIDS FOR THE PREV PACKAGE. WE WILL

NOT MAKE CHANGES TO THE PREV HAZARDS FOR THE UPDATE AS WELL. A

WEAK LOW OFF THE WASH COAST PER THE 12Z OPC-NCEP SFC ANALYSIS

HAS AN ASSOC COLD FRONT EXTENDING SW OVR FAR SE OREGON INTO THE

NRN CALIF WTRS. A LARGE HIGH PRES AREA WELL W OF THE CALIF WTRS

WILL PERSIST FOR THE NEXT SEVERAL DAYS. AT 12Z A SHIP LOCATED WELL

OFF THE SRN CALIF COAST...OR ROUGHLY 260 NM WSW OF PT CONCEPTION

REPORTED WINDS OF 33 KT. AFTER A QC CHECK HIS BIAS IS OVR 4 FT

TOO HIGH AND WITH NEARBY OBS NR 25 TO 30 KT...IT APPEARS THAT HE

IS REPORTING WINDS A LITTLE TOO HIGH AT 12Z. OVERALL...THE

CONTINUED INTERACTION BETWEEN THE HIGH AND A COASTAL AND INLAND

LOW PRES TROF WILL CONTINUE TO IMPACT WINDS AND SEAS OVR THE

REGION FOR THE NEXT SEVERAL DAYS...WITH THE BEST CHANCE FOR GALES

EXPANDING INTO THE SRN OREG AND FAR NRN CALIF OFF WTRS LTR THU

AND THU NITE.



SEAS...SEA HEIGHTS RANGE FROM NR 12 FT OFF THE CENTRAL CALIF COAST

TO 4 TO 5 FT OVR NW CALIF AND SRN OREG WTRS PER THE LATEST OBS. NO

MAJOR CHANGES APPEAR NECESSARY FROM THE PREV FCST. WE WILL MAKE

MINOR TWEAKS TO THE PREV GRIDS TO FIT A LITTLE BETTER WITH NEARBY

COASTAL AND TAFB FCSTS...FOR THE AM UPDATE.



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

PREVIOUS DISCUSSION...



THE LATEST MODEL GUIDANCE INDICATES THAT HIGH PRES CENTERED WELL

W OF THE NRN PZ6 WATERS CONTINUES TO COMBINE WITH INLAND LOW PRES

TO PRODUCE N TO NW WINDS UP TO 30 KT OFF THE COAST OF NRN AND

CENTRAL CALIFORNIA WITH THE STRONGEST CONDITIONS W OF POINT ARENA.

THESE CONDITIONS WILL REMAIN IN PLACE THROUGH WED AND THEN SHIFT N

TO OFF OF CAPE MENDOCINO BY WED NIGHT. GALE FORCE WINDS ARE

POSSIBLE ACROSS PORTIONS OF THE NRN AND CENTRAL PZ6 WATERS BY TUE

NIGHT ALREADY...BUT THE HIGH PRES W OF THE PZ6 WATERS SEEMS TO

STILL BE A BIT TOO FAR TO THE W. BY THU NIGHT WINDS ARE EXPECTED

TO INCREASE TO MINIMAL GALES OFF OF NRN CALIFORNIA AND SRN OREGON

AND THEN DECREASE AGAIN BY FRI. FARTHER N...ONE COLD FRONT WILL

MOVE ACROSS THE PZ5 WATERS TONIGHT...FOLLOWED BY ANOTHER WEAK COLD

FRONT TUE NIGHT. MEANWHILE...HURRICANE NEWTON IS EXPECTED TO

REMAIN S AND E OF THE SRN PZ6 WATERS TONIGHT INTO WED. THE 00Z

RUNS OF THE GFS AND ECMWF LOOK TO BE IN REASONABLE AGREEMENT

THROUGH SAT. FOR WIND GRIDS WILL USE THE GFS 10M WINDS WITH SOME

MINOR EDITS TO ADD GALES ACROSS THE NE PZ6/SE PZ5 WATERS BY THU

NIGHT. CURRENT WARNINGS LOOK REASONABLE AND FEW CHANGES ARE

EXPECTED 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.





.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.



$$



.FORECASTER MILLS/NOLT. OCEAN PREDICTION CENTER.

