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000
AGPN40 KWNM 221548
MIMPAC

MARINE WEATHER DISCUSSION FOR N PACIFIC OCEAN
NWS OCEAN PREDICTION CENTER WASHINGTON DC
848 AM PDT WED MAY 22 2013

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

AT 22/1200Z LOW PRES 1007 MB 90 NM N OF THE REGION WITH GALE FORCE
WINDS HAS A TROF XTNDG NW ALONG THE CANADA SEABOARD WITH ANOTHER
TROF STRETCHING SE THEN SW INTO THE NRN WTRS. INLAND LOW PRES 1001
MB OVR AZ/NV XTNDS A TROF ACRS CA STATE. HGH PRES 1036 MB CNTRED
540 NM DUE W OF THE OREG WTRS XTNDS A FRIDGE INTO THE GULF OF AK
AND HAS ANOTHER RIDGE INTO THE CNTRL AND SRN WTRS. A TIGHT PRES
GRDNT EXITS BTWN THE HGH AND THE TROF ALONG CA. GALE FORCE WINDS
ARE CONFINED TO THE ERN EDGE OF THE SRN WTRS NR THE INLAND TROF.
THE LAST ASCT PASS AT 0622Z MISSED THE ENTIRE REGION BUT THE PASS
HAD GALE FORCE WINDS NW OF THE NRN WTRS. THE SEAS ARE HGST OVR THE
NRN WTRS PEAKING AT 19 FT WITH ANOTHER PEAK OF 17 FT OVR THE ERN
EDGE OF THE CNTRL WTRS. THE NWW3 MULTI GRID FITS WELL WITH THE
CURR SEAS PATTERN AND SEEM QUITE REASONABLE WITH THE FCST. THE
GLBL MDLS ARE IN AGREMNT AND THEY SUGGEST THAT THE HGH PRES TO THE
W OF THE REGION WILL KEEP MOVING S AS IT WEAKENS. THE INLAND LOW
PRES TROF WILL REMAIN ACRS CA BUT THE PRES GRDNT WILL SLACKEN AS
THE HGH MOVES S. GALE FORCE WINDS WIL BE CONFINED TO THE ERN EDGE
OF THE CNTRL WTRS. WILL STAY WITH GFS FOR THIS UPDATE.

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

STG HIGH PRES IS SITU TO THE W OF THE WA/OR OFFSHR AND WL
GRADUALLY WEAKEN AS IT SHIFTS SWD THRU SUN AND BE LOCATED W OF
THE N AND CNTRL CA WTRS. MDT TO STG NWLY FLW PREVAILS ACRS MOST
AREAS OF THE OFFSHR WTRS WITH GALES OVR THE CNTRL AND SRN CA
WTRS. THERE WAS A SHIP OBS JUST W OF THE WA WITH NW WINDS TO 40
KT. THIS OBS HAS A GOOD QC HISTORY. 06Z SFC ANALYSIS HAS A STG
PRES GRAD WHICH SUPPORTS GALES ALG THE WRN AREAS OF THE WA WTRS.
MOST OF THE MDL GUID WITH THE EXCEPTION OF THE GEM INDICATES SUB
GALES SHUD DVLPG WITHIN THE NEXT SVRL HRS. PLAN ON LOOKING AT
09Z DATA AND WL DETERMINE WHETHER OR NOT TO HAV GALES CONTG INIT
OVR THE WA WTRS WITH UPCOMING UPDATED FCST. ELSW OVR THE ERN
AREAS OF THE CNTRL AND SRN CA WTRS GALES STILL APR TO LAST THRU
WED NGT. NWLY FLW BEGINS TO EASE OVR THE NRN OFFSHR WTRS THIS
LATE THIS MRNG INTO THE AFTN AS WK LOW PRES OVR WRN VANCOUVER
ISLD DRIFTS SWD WKNS PRES GRAD WHILE HIGH PRES GRADUALLY WKNS.
THE MULTIGRID WWIII SEEM TO SUBSIDE SEAS TOO QUICKLY OVR THE
WA/OR WTRS TDY INTO TNGT. PREFER THE ECMWF WV GUID WHICH SEEMS
MORE LIKELY. FURTHER S OVR THE CNTRL AND SRN CA WTRS MULTIGRID
WWIII AND ECMWF WV GUID ARE IN CLOSE AGRMT.

FOR THE UPDATE MDL GUID LOOKS SMLR THRU THE PD WITH MINOR
DEVIATIONS FM GFS PLANNED WITH ITS 30M BL WINDS PREFERRED
OVERALL. WL STRENGTHEN THE WINDS OVR THE CNTRAL AND SRN CA WTRS
LATE SAT INTO SUN WITH ECMWF SOMEWHAT STGR THE GFS.

SEAS...FOR SEAS PLAN ON BLENDING MULTIGRID WWIII WITH ECMWF WV
WITH GREATER WEIGHT TOWARDS ECMWF THRU PD.

EXTRATROPICAL STORM SURGE GUIDANCE...N/A.


.WARNINGS/FORECAST CONFIDENCE...PRELIMINARY. ANY CHANGES WILL BE
COORDINATED THROUGH AWIPS 12 PLANET CHAT OR BY TELEPHONE:

.PZ5 WASHINGTON/OREGON WATERS...
.CAPE FLATTERY TO CAPE LOOKOUT...NONE.
.CAPE LOOKOUT TO PT ST GEORGE...NONE.

.PZ6 CALIFORNIA WATERS...
.PT ST GEORGE TO PT ARENA...NONE.
.PT ARENA TO PT CONCEPTION...GALE TODAY INTO THU...HI CONFDNC.
.PT CONCEPTION TO GUADALUPE ISLAND...GALE TODAY INTO THU...HI
CONFDNC. GALE SUN...MDT CONFDNC
$$

.FORECASTER MUSONDA/ROWLAND. OCEAN PREDICTION CENTER.