Marine Interpretation Message
Issued by NWS

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AGPN40 KWNM 221508
MIMPAC

MARINE WEATHER DISCUSSION FOR N PACIFIC OCEAN
NWS OCEAN PREDICTION CENTER WASHINGTON DC
808 AM PDT MON SEP 22 2014

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

GOES IR IMGRY INDC A WKNG FRNTL BNDRY ACRS THE NRN OFSHR
WTRS...AND LGTNG DATA INDC A FEW STRIKES ALNG IT. THE CRNT DATA
INDC A MRGNLLY STABLE ENVRNMT...SO FRNTL FRCG IS EVIDENTLY
OVERCOMING THE LL STABILITY. THE GFS INDC THE FRNT WL WKN THRUT
THE DAY...SO WL HAVE MENTION OF TSTMS IN THE FCST...AND DCRS THEM
BY TNGT WITH THIS BNDRY.

THE IMGRY ALSO INDC A DVLPG LOW W OF THE OFSHR WTRS...MOVG TO THE
E. THE 12Z NCEP SFC ANALYS INDC THE SYS WL INTNSFY OVR THE NEXT 24
HOURS...AND THE WNDS ARE FCST TO INCRS TO HURCN FRC BY 12Z TMW
NEAR 140W. THE 00Z/06Z MDLS ALL INDC A STG LOW W OF THE
AREA...WITH A STG ASSOC H5 VORT. ALL BUT THE ECWMF INDC AT LEAST
STORM FRC AT THE SFC...THO THE ECMWF SHOWS 45 KT. HOWEVER...THE
ECMWF/GFS/NAM/UKMET ALL INDC BTWN 70 AND 80 KT AT 925 MB AT 12Z
TUE...AND IN THE UNSTABLE ENVRMT HURCN FRC SHUD MIX. THE MDLS ALL
INDC THE ASSOC CD FNT WL MOV INTO THE OFSHR WTRS TUE INTO TUE NGT.
THE SYS STILL LOOKS FAIRLY STG AT THAT POINT...AND THE GFS 30M
WINDS SHOW A SMALL AREA OF MRGNL GALES IN THE OUTER WATERS AHD OF
THE FRNT. THE REST OF THE GUID IS SMLR IN INTSTY...THO EVENLY
SPLIT ON THE INTNSTY OF THE WNDS BTWN THE NORMALLY CNSRVTV
ECMWF/UKMET AND THE STGR NAM/GEM SOLNS. THE PREV FCST TOOK A
CMPRMS SOLN AND WENT BLO GL FRC...SO WL STAY AT THAT ITNNSTY FOR
THE UPDATE...AS CONFDC IS ABT MDT. HOWEVER...CONFDC IS A BIT
HIGHER ON WED WITH GALES AS THE STG LOW PASSES JUST NW OF THE
AREA...AND THE STG PRES GRAD IN THE S QUAD PASSES OVR THE AREA.
THE PREV FCST HAD GALES ATTM...SO WL CONT IN THE UPDATE PKGT.

DIFFS CONT IN THE EXTENDED WITH THE TRACK OF THE NEXT SYS THRU THE
OFSHR WTRS. THE UKMET/ECWMF TAKE A MORE SRLY TRACK THAN THE GFS
AND GEM...ALTHO THE SYS IS A BIT WK. WITH THE HIGH
UNCERTAINTY...PREFERRING TO NOT MAKE ANY SIG CHANGES...SO WL STAY
CLOSE TO CONTINUITY.

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

LATEST SAT PIX AND CURRENT OBS INDICATE COLD FRONT MOVING ACROSS
PZ5 WATERS WITH SEAS RUNNING 4-7 FT ACROSS ENTIRE REGION.
ALTIMETER PASSES FROM 05 AND 03Z ALSO MATCH UP WELL WITH CURRENT
OB REPORTS. SCAT PASS FROM 05Z SHOWS MAINLY WINDS 10-15 KT WINDS
ACROSS OFFSHORE WATERS...WITH EMBEDDED WINDS TO 20 KT...MAX WINDS
TO 25 KT CURRENTLY INDICATED NR PT CONCEPTION. THE GLOBAL MODELS
ARE ALL IN VERY GOOD AGREEMENT THROUGHOUT THE PERIOD...BUT
ESPECIALLY OVR THE FIRST 3 DAYS. AFTER 72 HRS SOME DIFFERENCES
BEGIN TO EMERGE...THE GFS/CMC TAKE THE MAIN LOW CENTER NW OF THE
WASHINGTON WATERS...WHILE THE ECMWF DIGS THE LOW SE INTO THE
WATERS...ALBEIT IN A WEAKENED STATE BY THAT POINT. THE ULMET IS
PROBABLY A GOOD COMPROMISE SOLN AND DIPS THE LOW SE INTO THE
WASHINGTON WATERS...BUT NOT AS FAR SE A THE ECMWF INDICATES. WHEN
POP THE GRIDS WILL USE THE 10M GFS THROUGHOUT THE PERIOD...EXCEPT
FOR THE STRETCH FROM 00Z WED THROUGH 21Z WED WHERE I DECIDED TO
USE THE ECMWF...WHICH IS A LITTLE QUICKER IN BRINGING GALES TO THE
PZ5 WATERS BEHIND THE INITIAL FRONTAL BOUNDARY...AS THE STRONG
LOW PRESSES E. AS FAR AS THE SEAS GO...THE WW3 LOOKS REASONABLE
THROUGHOUT. WILL POP WAVE GRIDS WITH CORRESPONDING MODEL GUID TO
MATCH THE WINDS. WILL MAKE SOME ADJUSTMENTS TO GRIDS ALONG THE
COASTAL BORDER IN ORDER TO SHOW SOME CONSISTANCY./

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


.WARNINGS...PRELIMINARY.

.PZ5 WASHINGTON/OREGON WATERS...
.PZZ900...OUTER WATERS FROM CAPE FLATTERY TO CAPE SHOALWATER...
     GALE TUE NIGHT.
     GALE POSSIBLE WED.
.PZZ905...OUTER WATERS FROM CAPE SHOALWATER TO CAPE LOOKOUT...
     GALE TUE NIGHT.
     GALE POSSIBLE WED.
.PZZ910...OUTER WATERS FROM CAPE LOOKOUT TO FLORENCE OR...
     GALE TUE NIGHT.
     GALE POSSIBLE WED.
.PZZ915...OUTER WATERS FROM FLORENCE OR TO POINT ST. GEORGE...
     GALE TUE NIGHT.
     GALE POSSIBLE WED.

.PZ6 CALIFORNIA WATERS...
     NONE.

$$

.FORECASTER KELLS/SHAW. OCEAN PREDICTION CENTER.


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