

413 

AGPN40 KWNM 032148

MIMPAC



MARINE WEATHER DISCUSSION FOR N PACIFIC OCEAN

NWS OCEAN PREDICTION CENTER WASHINGTON DC

248 PM PDT SAT SEP 3 2016



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

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



THRU THU NIGHT THE PATTERN OVER THE ERN PAC IS EXPECTED TO CHANGE

LITTLE AS A SERIES OF MID/UPR SHRTWV TROFS MOV OVER A BROAD UPR

RIDGE W OF THE WATERS AND PASS SE OVER OR JUST N OF THE PZ5

WATERS AND MOV INLAND OVR PAC NW. THE FIRST OF THESE APPEARS IN

GOES W/V IMAGERY OVR WASHINGTON WATERS WITH WK SFC REFLECTIONS IN

FORM OF SFC TROF OVR VANCOUVER ISL AND A WK LOW NR 42N134W. THE

EFFECT OF THESE IS TO KEEP THE ERN PAC HIGH WELL W OF WATERS AND

WINDS STAYING BELOW GALE FORCE IN OFSHR WTRS. WINDS COULD APPROACH

GALE FORCE OFF NRN CA ESPCLY LATE AFTERNOONS AND EVENINGS INTO TUE

NIGHT AS THE PERSISTENT THERMAL TROF OVR CA STRENGTHENS

DIURNALLY. FOR TUE NIGHT INTO WED NIGHT MDLS SHOW THE EPAC HIGH

PRES SHIFTING E AND BUILDING A RIDGE INTO PZ5 WTRS WITH SOME

ENHANCEMENT OF THE GRADIENT BETWEEN THE CSTL TROF AND RIDGE. WIND

CONDS APPR TO MAXIMIZE OFF CENTRAL AND NRN CA ARND THAT TIME. FOR

THE NEW FCST GRIDS POPULATED THE FIRST PERIOD WITH THE 12Z GFS 30M

WINDS AS THESE APPEAR REPRESENTATIVE WHEN COMPARED TO 17Z-19Z HIGH

RES ASCAT-B PASSES. FOR THE REMAINDER OF THE FCST USED A

COMPROMISE 50/50 BLEND OF 12Z GFS 10M AND 30M WINDS WHILE LIMITING

GRID VALUES TO 32 KT OR LESS DURING PERIOD OF STRONGEST WINDS. THE

12Z CMC GEM HAS STRONGEST CONDS AND SHOWS GALES EXTENDING INTO

OFSHR WTRS WED NIGHT THRU THU NIGHT AND EVEN BEYOND WHEREAS 12Z

ECMWF/UKMET SHOW NO GALES AND 10M WINDS UP TO 30 KT. HENCE THE NEW

FCST WILL CONTINUE TO CARRY NO HEADLINES.



THE 12Z ENP NWW3 LOOKS REASONABLE WITH THE SEAS AND WILL BE

FOLLOWED FAIRLY CLOSELY THRU THU NIGHT...WITH 12Z ECMWF WAM CLOSE

WI A FOOT.



EXTRATROPICAL STORM SURGE GUIDANCE...N/A.



.WARNINGS...PRELIMINARY.



.PZ5 WASHINGTON/OREGON WATERS...

     NONE.



.PZ6 CALIFORNIA WATERS...

     NONE.



$$



.FORECASTER BANCROFT. OCEAN PREDICTION CENTER.

