Marine Interpretation Message
Issued by NWS

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000
AGPN40 KWNM 211449
MIMPAC

MARINE WEATHER DISCUSSION FOR N PACIFIC OCEAN
NWS OCEAN PREDICTION CENTER WASHINGTON DC
649 AM PST FRI NOV 21 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 STG LOW PRES SYS IN THE EPAC...CTRD OVR THE
GULFAK. BIGGEST CONCERN WITH THIS SYS REMAINS THE CHANNELING FLOW
BTWN THE FRNT AND THE COAST. EARLIER ASCAT DATA FM 06Z MISSED THE
REGION BTWN THE FRNT AND THE COAST...BUT THE MORE RECENT RSCAT
PASSES FM 10 AND 12Z SHOW A LRG AREA OF GALES BTWN THE FRNT AND
COAST FM THE WAS COAST UP TO HAIDA GWAII...THO MANY W OF THE WAS
COAST ARE RAIN-FLAGGED. CRNT SFC RPRTS CORROBORATE THE RSCAT WNDS
DATA...AND GFS 30M WNDS SEEM INIT OK WHEN COMPARED WITH IT. THE
MDLS INDC THE LL CONFLUENCE WL MOV S AS THE FRNTL BNDRY MOVES TWD
THE COAST...AND GFS WNDS INDC GL TO STRM FRC WNDS AHD OF IT. THE
REST OF THE MDLS AGREE FAIRLY WELL ON THE TMG AND INTSTY OF THE
FRNTL BNDRY...SO CONFDC WITH GALES IN THE OFSHR WTRS IS HIGH ATTM.
AS A RESULT...WL CONT WITH PREV THINKING...AND USE 30M GFS WNDS
FOR THE FCST WITH THIS SYS.

THE MDLS ALSO INDC A SHRTWV TROF WL MOV THRU THE AREA SAT NGT INTO
SUN...AND INCRS THE WNDS OVR THE PZ5 WTRS TO GL FRC. THE ENERGY IS
CRNTLY OUT NR 170W AND SEEMS FAIRLY POTENT ATTM...AS THE CRNT
LGTNG DATA INDC TSTMS ACTIVITY IN THE CAA. THE GFS INDC 45 KT OVR
THE WAS WTRS. THIS SEEMS A BIT STG...AS THE REST OF THE GUID ONLY
SHOWS ABT 35 KT. ATTM FEELING THAT A COMPRMS SOLN IS BEST...SO WL
CARRY WNDS TO 40 IN THE NRN WAS WTRS IN THAT TIME FRAME.

OTRW...MDLS AGREE FAIRLY WELL INTO MON...THEN DVRG SOME WITH A
FRNTL BNDRY/LOW OVR THE NRN PTTN MON AND TUE. PREV FCST FAVORED
GFS SOLN...BUT ECWMF SEEMS TO HAVE MORE SUPPORT FM REST OF
GUID...SO WL SWITCH FAVOR THE 00Z ECWMF IN THE EXTENDED PORTION OF
THE FCST. WL ALSO SWITCH TO ECMWF WAM TO BETTER REFLECT WX MDL
TRENDS.

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

THE 06Z SFC ANALYSIS INDICATED A WEAKENING COLD FRONT OVER THE
CENTRAL CA WATERS...WITH STRENGTHENING LOW PRES NEAR 44N143W AND
STATIONARY FRONT EXTENDING NE TO W OF THE WA OFFSHORE WATERS.
SEVERAL ASCAT PASSES FROM AROUND 0500Z AND 0545Z WITH VERY GOOD
COVERAGE OVER OFFSHORE AND COASTAL WATERS INDICATED WINDS MOSTLY
10 TO 20 KT...WITH SOME 20 TO 25 KT NOTED OVER THE FAR WRN
WASHINGTON WATERS...WITH GALES NW OF THE WA WATERS TO THE W OF
QUEEN CHARLOTTE ISLANDS.

THE 00Z MODELS CONTINUE TO BE IN VERY GOOD AGREEMENT THROUGH ABOUT
THE FIRST HALF OF THE FCST PERIOD...WITH MODEL AGREEMENT DROPPING
SHARPLY MON AND CONTINUING THROUGH THE END OF THE FCST PERIOD. FOR
THE SHORT TERM PERIOD FROM TODAY THROUGH ABOUT 12Z MON...THE
MODELS ARE INDICATING REMARKABLY FEW MAJOR DIFFERENCES CONSIDERING
THE VERY ACTIVE PATTERN. A SERIES OF STRONG SYSTEMS WILL IMPACT
MAINLY THE WA/OR WATERS THROUGH SUN MORNING. THE LOW PRES W OF THE
AREA MENTIONED ABOVE WILL TRACK NE ACROSS THE FAR NRN OR AND SE WA
WATERS TODAY WITH COLD FRONT MOVING ACROSS THE AREA BEFORE MOVING
INLAND LATER THIS EVENING. THE NEXT SYSTEM WILL IMPACT THE AREA
SAT NIGHT INTO SUN AS LOW PASSES N OF THE WA WATERS. WILL POPULATE
GRIDS USING THE 30M GFS WINDS AS THERE SHOULD BE AMPLE MIXING TO
ALLOW STRONGER WINDS TO REACH THE SURFACE WITH BOTH SYSTEMS. THIS
WILL RESULT IN FEW CHANGES TO PREVIOUS WARNING HEADLINES.
LOOKING AHEAD TO MON THROUGH TUE NIGHT...THERE CONTINUE TO BE
DIFFERENCES WITH HANDLING OF NEXT LOW AND FRONT. THE GFS/UKMET
APPEAR TO BE IN REASONABLE AGREEMENT WITH THE ECMWF NOW KEEPING
WINDS SRLY THROUGH THE PERIOD. WILL GO CLOSER TO GFS DURING THIS
PERIOD.

.SEAS...THE 06Z SEA STATE ANALYSIS INDICATED THAT OBSERVED SEAS
MATCHED UP WELL WITH BOTH THE MWW3/ECMWF WAM VALUES WITH
DIFFERENCES MOSTLY A FT. FOR TODAY THROUGH SAT...WILL USE THE MWW3
VALUES TO POPULATE GRIDS. THEN BEGINNING 00Z SUN AND CONTINING
THROUGH SUN NIGHT WILL USE A 70/30 ECMWF/MWW3 BLEND AS THE MWW3
STILL CONTINUES TO BE QUITE A BIT HIGHER THAN THE ECMWF WAM
VALUES. FOR 12Z MON AND BEYOND WILL USE 50/50 BLEND OF
ECMWF/MWW3.

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


.WARNINGS...PRELIMINARY.

.PZ5 WASHINGTON/OREGON WATERS...
.PZZ800...INNER WATERS FROM CAPE FLATTERY TO CAPE SHOALWATER...
     GALE TODAY.
     GALE SAT NIGHT.
     GALE POSSIBLE SUN.
.PZZ900...OUTER WATERS FROM CAPE FLATTERY TO CAPE SHOALWATER...
     GALE TODAY.
     GALE SAT NIGHT.
     GALE POSSIBLE SUN.
.PZZ805...INNER WATERS FROM CAPE SHOALWATER TO CAPE LOOKOUT...
     GALE TODAY.
     GALE SAT NIGHT.
.PZZ905...OUTER WATERS FROM CAPE SHOALWATER TO CAPE LOOKOUT...
     GALE TODAY.
     GALE SAT NIGHT.
.PZZ810...INNER WATERS FROM CAPE LOOKOUT TO FLORENCE OR...
     GALE TODAY.
     GALE SAT.
.PZZ910...OUTER WATERS FROM CAPE LOOKOUT TO FLORENCE OR...
     GALE TODAY INTO SAT.
.PZZ815...INNER WATERS FROM FLORENCE OR TO POINT ST. GEORGE...
     GALE TODAY.
     GALE SAT.
.PZZ915...OUTER WATERS FROM FLORENCE OR TO POINT ST. GEORGE...
     GALE TODAY INTO SAT.

.PZ6 CALIFORNIA WATERS...
.PZZ920...OUTER WATERS FROM POINT ST. GEORGE TO POINT ARENA...
     GALE TODAY.

$$

.FORECASTER KELLS/KOSIER. OCEAN PREDICTION CENTER.


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