000
AGPN40 KWNM 181443
MIMPAC
MARINE WEATHER DISCUSSION FOR N PACIFIC OCEAN
NWS OCEAN PREDICTION CENTER WASHINGTON DC
743 AM PDT SAT MAY 18 2013
.FORECAST DISCUSSION: MAJOR FEATURES/WINDS/SEAS/SIGNIFICANT
.WEATHER FOR THE NORTH PACIFIC N OF 30N AND E OF 150W.
GOES IR IMGRY INDC A WK CDFNT ACRS TH N PTTN ATTM...AND HIGH PRES
W OF THE C CAL WTRS. THE WV IMGRY INDC A SLOWLY AMPLIFYING UPR RDG
NR 135W...AND DRIFTING E. THE GUID INDC THE H5 HGTS WL RISE OVR
THE CAL COAST...ENHANCING THE THRML TROF. GALES ARE XPCTD TO BEGIN
SUN AFTN IN THE GRAD NR PT ARENA...ALTHO MDLS ARE MRGNL AND THE
GFS HAS BEEN TRENDING WKR. PLAN ON STILL CARRYING GALES...THO
CONFDC IS LOW TO MDT WITH THEM.
GFS CONT TO BE OUTLIER WITH THE SYS ON TUE...AS IT TAKES THE LOW
THRU THE PZ5 WTRS AND INCRS THE WNDS TO GL FRC. THE REST OF THE
GUID FAVORS A TRACK THAT KEEPS THE GALES W OF THE AREA...AND TAKES
THE SFC LOW SW OF THE GFS TRACK. UPR ENERGY INDC THE ASSOC SHRTWV
FM SW WL GET PICKED UP BY UPR TROF...THO ASIDE FM GFS REST OF GUID
DIGS THE TROF A LTL DEEPER. ATTM PREFERRING THE ECMWF SOLN ON
TUE...AS CONFDC WITH GALES IS VRY LOW. OTRW CD SURGE FM UPR TROF
WL ENHANCE MXG ALNG COAST WED...AND WNDS XPCTD TO INCRS TO GL FRC
OFF CAL COAST AGAIN...WITH LOW TO MDT CONFDC. WL HAV GALES OVR THE
NRN AND C CAL WTRS LATE TUE AND WED.
SEAS...STAYING CLOSE TO MWW3 SOLN...ALTHO PREFERRING ECMWF WAVE
MDL TUE OVR PZ5 WITH GFS WNDS OVERDONE.
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PREVIOUS DISCUSSION...
OPC 06Z SFC ANALYSIS DEPICTS A FRONTAL SYS OVER THE PZ05 WTRS WITH A
1027 MB HIGH CENTERED NEAR 33N137W. PER RECENT OBS...WINDS HAVE
BEEN IN THE 10 TO 20 KT RANGE. HAVE NO RECENT ASCAT/OSCAT PASSES.
OVER THE NEXT DAY OR SO EXPECT GENERALLY QUIET CONDS TO PREVAIL
AS AFOREMENTIONED FRONT WEAKENS WHILE TRAVERSING THE WTRS.
DO NOT SEE A REASON TO STRAY FROM MENTION OF GALES FOR PARTS OF
THE PZ06 WTRS ON SUN INTO MON AND AGAIN TUE INTO WED AS ERN PAC
HIGH INTERACTS WITH TROF EXTENDING N ALONG THE W COAST. THOUGH
CONFDC WILL REMAIN AT MDT GIVEN THE SLIGHTLY WEAKER GFC SOLN THIS
RUN.
W/BETTER AGREEMENT BETWEEN THE GFS AND ECMWF AND TO A LESSER
EXTENT THE SRN OUTLIER UKMET...AM MORE CONFDT W/APPENDING GALES
TO THE PZ05 WTRS TUE. THESE GALES WILL BE ASSOCIATED WITH A
VIGOROUS AND ANOMALOUS COLD CORE CLOSED LOW PRES SYS. IN
FACT...WILL LIKELY NEED TO ADD THUNDERSHOWER WORDING TO THE
FORECAST FOR THE TUE INTO WED TIME FRAME IN THE SUN EVE AND
SUBSEQUENT FORECASTS.
A WEAKER LOW PRES SYS APPEARS TO DROP S INTO THE PZ05 WTRS ON WED
BUT WITH LITTLE IN THE WAY OF SIG WX.
SEAS...THE 00Z MWW3 AND ECMWF WAVE MDL SOLNS ARE INIT WELL WITH
SEAS UP TO 7 FT OVR THE EPAC. GIVEN SIMILAR SOLN BETWEEN THE TWO
WAVE MODELS WITH MINOR DIVERGENCE EVEN AT DAY FIVE AM INCLINED TO
USE THE WW3 AS A MATTER OF CONSISTENCY.
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...GALE SUN INTO MON...THEN TUE AND
WED...LOW TO MDT CONFDC.
.PT ARENA TO PT CONCEPTION...GALE SUN INTO MON...THEN TUE AND
WED...LOW TO MDT CONFDC.
.PT CONCEPTION TO GUADALUPE ISLAND...NONE.
$$
.FORECASTER KELLS/LEE. OCEAN PREDICTION CENTER.