Marine Interpretation Message
Issued by NWS

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000
AGPN40 KWNM 290344
MIMPAC

MARINE WEATHER DISCUSSION FOR N PACIFIC OCEAN
NWS OCEAN PREDICTION CENTER WASHINGTON DC
844 PM PDT SAT MAY 28 2016

.FORECAST DISCUSSION: MAJOR FEATURES/WINDS/SEAS/SIGNIFICANT
.WEATHER FOR THE NORTH PACIFIC N OF 30N AND E OF 150W.

THE 00Z OPC SFC ANALYSIS SHOWS A RELAXED PRES GRADIENT NOW OVER
MOST OF THE FORECAST WATERS AND THE INLAND TROUGH OVER CA HAS NOW
WEAKENED. THE MAX WINDS ARE STILL OVER THE ERN PARTS OF THE
CENTARL WATERS AT 30 KT. THE LAST ASCAT PASS WAS AT 1839Z AND IS
DESCRIBED BELOW. THE SEAS ARE HIGHEST OVER THE ERN PARTS WITH 11
FT PEAKS AND THEY RANGE BETWEEN 3 AND 8 FT ELSEWHERE. THE GLOBAL
MODELS ARE STILL IN GUD AGREEMENT AND THEY ALL AGREE ON KEEPING
THE HGH PRES TO THE W AND THEN MOVE INTO INTO THE WATERS AND WINDS
WILL REMAIN BELWO GALE FORCE THROUGH THE PERIOD.

-----------------------------------------------------------------
PREVIOUS DISCUSSION...

THE 18Z OPC SFC ANALYSIS SHOWS A PINCHED GRADIENT REMAINS OVER
THE NRN PZ6 WATERS BETWEEN AN INLAND TROUGH OVER CA AND SFC HIGH
PRES W OF THE WATERS. AN ASCAT-B PASS AROUND 1752Z CONFIRMED A
SWATH OF 25-30 KT WINDS OVER THE NRN/CENTRAL CA WATERS...MATCHING
UP WELL WITH THE CURRENT FCST GRIDS. ELSEWHERE A WEAK COLD FRONT
ASSOCIATED WITH A 1012 MB LOW OVER VANCOUVER ISLAND EXTENDS SWD
ACROSS THE PZ5 WATERS.

WITH A FAIRLY QUIET PATTERN OVERALL...THE GLOBAL MODELS REMAIN IN
GOOD AGREEMENT THROUGH MUCH OF THE FCST PERIOD. HIGH PRES WILL
MOVE E AND THEN NE OVER THE PZ5 WATERS BY MON...WITH NLY FLOW OF
20-30 KT PERSISTING OVER THE NRN CA WATERS BEFORE EXPANDING INTO
THE SRN OR WATERS MON INTO EARLY TUE. THE 12Z GFS/ECMWF/NAM ALL
KEEP THE STRONGEST NLY WINDS OVER THE COASTAL WATERS...SO NO
MARINE HEADLINES FOR THE OFFSHORE ZONES ARE NEEDED ATTM. USED A
BLEND OF THE 30M/10M GFS WINDS TODAY THROUGH TUE MORNING TO
MAINTAIN ENHANCED NLY FLOW OVER THE WATERS WHILE KEEPING THE WINDS
BELOW GALE FORCE.

HIGH PRES OFF THE WA COAST ON TUE WILL SLIDE SW THROUGH WED WITH A
RIDGE AXIS EXTENDING ACROSS THE PZ5 WATERS...DRIFTING E OVER THE
NRN PZ6 WATERS BY THU. THIS WILL RESULT IN A WEAKENING GRADIENT
OVER THE WATERS BY MID WEEK WITH WIND SPEEDS DIMINISHING TO 5-15
KT ACROSS MUCH OF THE AREA. A LOW PRES SYSTEM APPROACHING FROM THE
W WILL TRACK NW OF THE PZ5 WATERS LATE THU/EARLY FRI. THE
GFS/ECMWF ARE IN EXCELLENT AGREEMENT WITH REGARDS TO THE POSITION
OF THIS FEATURE...SO LEANED TOWARD THE ECMWF SOLUTION WHICH IS A
BIT MORE CONSERVATIVE WITH THIS LOW IN THE LONG RANGE.

.SEAS...GIVEN THE GREAT AGREEMENT BETWEEN THE GFS/ECMWF FOR MUCH
OF THE FCST PERIOD...THE WAVE OUTPUTS WERE VERY SIMILAR AS WELL.
USED A 50/50 BLEND OF THE WW3/ECMWF WAM THROUGH TUE MORNING...THEN
FAVORED THE WAM THROUGH THU NIGHT TO REMAIN CONSISTENT WITH THE
WIND FCST.


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



.WARNINGS...PRELIMINARY.

.PZ5 WASHINGTON/OREGON WATERS...
     NONE.

.PZ6 CALIFORNIA WATERS...
     NONE.

$$

.FORECASTER MUSONDA/REINHART. OCEAN PREDICTION CENTER.



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