

021 

AGPN40 KWNM 011440

MIMPAC



MARINE WEATHER DISCUSSION FOR N PACIFIC OCEAN 

NWS OCEAN PREDICTION CENTER WASHINGTON DC

740 AM PDT MON 1 AUG 2016 



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

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



06Z GFS AND 06Z/12Z NAM WERE GENERALLY CONSISTENT WITH THEIR 

RESPECTIVE PREVIOUS RUNS. LATEST MODELS CONTINUE IN GOOD 

AGREEMENT FOR THE NEXT SEVERAL DAYS THAT HIGH PRES WILL 

STRENGTHEN SOMEWHAT AND DRIFT SLIGHTLY EASTWARD TONIGHT THROUGH 

MIDWEEK...WITH MARGINAL GALES LIKELY DEVELOPING IN THE FAVORED 

COASTAL/INNER OFFSHORE ZONES OFF NRN CALIFORNIA LATE TUE AND 

PERSISTING INTO THU NIGHT. THE PREVIOUS OPC WIND GRIDS LOOK 

REASONABLE AND WILL NOT BE MAKING ANY SIGNIFICANT ADJUSTMENTST 

TO THEM IN THIS MORNINGS UPDATES.  



THE 00Z/06Z WAVEWATCH III AND 00Z ECMWF WAM ARE WELL INTIALIZED 

WITH WAVE HEIGHTS ACROSS THE E PACIFIC THIS MORNING. OPC WAVE 

HEIGHT GRIDS ARE MOSTLY BASED ON THE 00Z WW3. HOWEVER GRIDS WERE 

ADJUSTED UPWARD BY ABOUT 10 TO 15 PERCENT ACROSS AREAS WITH 

GALES FORECAST OFF NRN CALIFORNIA. 



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

...PREVIOUS DISCUSSION...



THE LTST NCEP SFC ANALYSIS INDC A STG PREG GRAD ACRS THE NRN CAL 

OFSHR WTRS...AS A WKNG HIGH PRES RDG ACRS PZ5 INTERACTS WITH A 

LOW PRES TROF OVR CENTRAL CAL. THE 05Z ASCAT PASSES INDC A LARGE 

AREA OF 30 KT WINDS IN THE NRN CAL WTRS...WITH A VERY SMALL AREA 

OF GALE FRC WINDS IN THE COASTAL WTRS. CRNT SFC RRPTS STILL INDC 

UP TO 30 KT IN THE OFHSR WTRS...BUT SINCE GALES WERE IN THE PREV 

FCST IN ZONE PZZ820...PLANNING ON STARTING OFF WITH 30 KT IN THE 

OFSHR WATERS. THE 00Z GFS INDC THE WINDS WL SLOWLY WKN TDA...AS 

THE RDG AND TROF WKN. THE REST OF THE 00Z MODELS AGREE FAIRLY 

WELL WITH THE 00Z OVER THE NEXT 24 HOURS WITH THE OVERALL 

PTTN...AND ON THE STRENGTH OF THE PRES GRAD AND ASSOC WINDS...SO 

PLANNING ON USING A BLEND OF THE 10M/30M WINDS WHICH SEEM 

REPRESENTATIVE...BUT WL CAP AT 30 KT. 



OTRW...THE 00Z GFS/ECMWF/UKMET AGREE VRY WELL THRUT THE 

REMAINDER OF THE FCST PD...AND INDC A WK CDFNT JUST NW OF THE 

OFSHR WATERS WL MOV INTO THE E PAC AND DSIPT OVR PZ5 TDA...FLWD 

BY A LOW PRES TROUGH TNGT. THE WK CD SURGE BEHIND THE FRNTS SHUD 

BE ENUF TO LOWER STATIC STABILITY...AND ALLOW STRONGER WINDS 

ALOFT TO MIX DN TWD THE SFC. THE 00Z GFS INDC 35 TO 40 KT AT 925 

MB FROM TUE NGT INTO FRI...WHICH SETS UP AN AREA OF VERT SHEAR 

JUST W OF CAPE MENDOCINO. IN ADDITION...THE 00Z MODELS ALL INDC 

AN H5 VORT CRNTLY 35N135W WL DRIFT E TWD THE COAST BY WED 

NGT...AND ENHANCE THE THERMAL TROF OVER THE CAL INTERIOR. THE 

GFS HAS BEEN CONSISTENTLY INDCG GALES FOR PZZ820 TUE NGT INTO 

THU NGT...AND THE REST OF THE 00Z GUID INDC ABT THE SAME...THO 

THE 00Z GEM IS A BIT STGR...AND IS A STG OUTLIER. THE PREV FCST 

HAD GALES CONSISTENT WITH THE GFS...AND CONFDC IS MDT TO 

HIGH...SO PLANNING ON MAINTAINING WRNG IN THE NEXT PKG. OTRW WL 

USE 00Z FOR THE REMAINDER OF THE FCST...AS IT IS WELL SUPPORTED 

BY THE REST OF THE 00Z MODELS. 



.SEAS...THE 00Z WAVEWATCH-III AND ECMWF WAM MODELS ARE INIT A FT 

OR TWO LOW IN THE NRN CAL WTRS...BUT OTRW OK IN THE E PAC. THE 

MDLS AGREE WELL THRUT THE FCST PD...AND SEEM FAIRLY RSNBL WITH 

THE NEXT ROUND OF GALES TUE NGT INTO THU NGT...THO A TAD 

LOW...SO WL ADJUST SLIGHTLY HIGHER IN THE NRN CAL WATERS. 



.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 TUE NIGHT.

     GALE POSSIBLE WED INTO THU NIGHT. 



$$ 



.FORECASTER CLARK/KELLS. OCEAN PREDICTION CENTER.

