Marine Interpretation Message
Issued by NWS

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AGNT40 KWNM 201302
MIMATN

MARINE WEATHER DISCUSSION FOR N ATLANTIC OCEAN
NWS OCEAN PREDICTION CENTER WASHINGTON DC
902 AM EDT SUN APR 20 2014

.FORECAST DISCUSSION: MAJOR FEATURES/WINDS/SEAS/SIGNIFICANT
.WEATHER FOR THE NORTH ATLANTIC OCEAN W OF 50W FROM 30N TO 50N.

LOW PRES NR 31N77W PER THE LATEST SFC OBS FM BUOYS 41025...
41013...AND 41036 HAS A GALE FORCE NELY GRADIENT EXTENDING ACRS
ITS NW AND N QUADRANTS ACRS THE SRN AND CNTRL NT2 WTRS PRETTY MUCH
AS PREVLY FCSTD. MAX SEAS IN THIS GRADIENT ARE IN THE 14-17 FT
RANGE WHICH ARE BEING HANDLED BETTER BY THE 00Z ECMWF WAM THAN THE
LOWER 06Z WAVEWATCH III.

OVER THE SHORT TERM...THO THE LATEST MDLS DIFFER SMWHT ON THEIR
FCST TRACKS OF THE SFC LOW THEY FCST SMLR ASCD FCST GRADIENTS.
OVERALL WL USE A BLENDED 00Z/06Z GFS AND 00Z ECMWF SOLUTION FOR
THIS SYSTEM (FCSTG THE LOW TO PASS E OF THE NT2 WTRS ON MON) AND
AS A RESULT...SMLR TO THE PREV NT2 FCST...WL FCST ASCD WINDS BCMG
SUBGALE THRUT ON MON. SO OTHERWISE NO SIG SHORT TERM CHNGS ARE
PLANNED TO THE PREV OFSHR FCST PACKAGE.

IN THE LONG RANGE...OVERALL THE 06Z GFS REMAINS IN RSNBLY GOOD
AGRMT VS ITS PREV 00Z RUN IN FCSTG A NRN STREAM DVLPG SFC LOW MOVG
OFSHR INTO THE NRN WTRS TUE NITE...THEN PASSING SLOWLY E OF THE
NRN OFSHR WTRS WED INTO THU WHILE SLOWLY INTENSIFYG. FOR THE
STRONG NNWLY GRADIENT FCST TO DVLP BEHIND THIS LOW AND ITS ASCD
COLD FROPA WL NOT MAKE ANY MAJOR CHANGES TO THE PREVLY USED 50/50
BLEND OF THE 00Z GFS AND 00Z ECMWF AND AS A RESULT WITH MOD FCST
CONFIDENCE WL CONT TO FCST PSBL GALES TO DVLP ACRS THE ERN NT1
AND NE NT2 WTRS WED NITE INTO THU NITE. SO PLAN ON MAKING ONLY
MINOR LONG RANGE CHNGS IN THE NEXT OFSHR FCST PACKAGE.



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

A SLOW MOVING AREA OF LOW PRES WILL BE EFFECTING MUCH OF THE NT2
WATERS OVER THE NEXT COUPLE OF DAYS AS N TO NE FLOW PERSISTS WITH
STRONGEST WINDS VCNITY OF THE THE THE GULF STREAM. THE THE GLOBAL
MODELS ARE IN PRETTY GOOD AGREEMENT WITH THIS FEATURE WITH THE
DIFFERENCES MAINLY IN THE THE DETAILS AND STRENGTH OF THE BL
WINDS. LATER IN THE WEEK AN AREA OF LOW PRES WILL MOVE OFF THE NE
CST AND INTENSIFY E OF THE NT1 WATERS...AGAIN BOTH THE GFS/ECMWF
ARE IN FAIRLY GOOD AGREEMENT WITH THIS FEATURE. WHEN POPULATING
THE GRIDS I USED THE 30M GFS WINDS FOR THE FIRST PART OF THE
PACKAGE...TRANSITIONING TO THE 10 M WINDS LATER WHEN MORE STABLE
CONDITIONS ARE EVIDENT. FOR DAYS 5-7 I USED A 50/50 BLEND OF THE
GFS/ECMWF FOR THE WINDS IN ORDER TO HEDGE MY BETS.

.SEAS...THET SEAS LOOKED OK IN GENERAL. I USED A 50/50 BLEND OF
THE WW3 AND ECMWF WAVE GUIDANCE THROUGHOUT THE FCST PERIOD. I
MODIFIED THE SEAS SLIGHTLY IN CERTAIN AREAS WHERE IT APPEARED TOO
HIGH BY ABOUT A FOOT OR SO.

.EXTRATROPICAL STORM SURGE GUIDANCE...BOTH THE ESTOFS AND ETSS
LOOK REASONABLE GIVEN THE OVERALL AGREEMENT WITH THE GFS.


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

.NT1 NEW ENGLAND WATERS...
.ANZ800...GULF OF MAINE...
     GALE POSSIBLE WED NIGHT INTO THU.
.ANZ900...GEORGES BANK WEST OF 68W...
     GALE POSSIBLE WED NIGHT INTO THU NIGHT.

.NT2 MID ATLC WATERS...
.ANZ920...BALTIMORE CANYON TO THE GREAT SOUTH CHANNEL...
     GALE TODAY.
.ANZ905...THE GREAT SOUTH CHANNEL TO THE HAGUE LINE...
     GALE POSSIBLE WED NIGHT INTO THU NIGHT.
.ANZ910...EAST OF THE GREAT SOUTH CHANNEL AND SOUTH OF 39N...
     GALE POSSIBLE THU INTO THU NIGHT.
.ANZ825...INNER WATERS FROM BALTIMORE CANYON TO CAPE CHARLES LIGHT...
     GALE TODAY.
.ANZ828...INNER WATERS FROM CAPE CHARLES LIGHT TO CURRITUCK BEACH LIGHT...
     GALE TODAY INTO TONIGHT.
.ANZ925...OUTER WATERS FROM BALTIMORE CANYON TO HATTERAS CANYON...
     GALE TODAY INTO MON.
.ANZ830...INNER WATERS FROM CURRITUCK BEACH LIGHT TO CAPE HATTERAS...
     GALE TODAY INTO TONIGHT.
.ANZ833...INNER WATERS FROM CAPE HATTERAS TO CAPE FEAR...
     GALE TODAY INTO TONIGHT.
.ANZ930...OUTER WATERS FROM HATTERAS CANYON TO CAPE FEAR...
     GALE TODAY.
.ANZ835...INNER WATERS FROM CAPE FEAR TO 31N...
     GALE TODAY INTO TONIGHT.

$$

.FORECASTER VUKITS/SHAW. OCEAN PREDICTION CENTER.


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