Marine Interpretation Message
Issued by NWS

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000
AGNT40 KWNM 281306
MIMATN

MARINE WEATHER DISCUSSION FOR N ATLANTIC OCEAN
NWS OCEAN PREDICTION CENTER WASHINGTON DC
806 AM EST SAT FEB 28 2015

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

AS STRONG HIGH PRES SLOWLY BUILDS E TWDS THE NRN MID ATLC COAST
THE NELY GRADIENT TO ITS S CONTS TO SLOWLY STRENGTHEN PRETTY MUCH
AS PREVLY EXPECTED. WITH BUOYS 41004 AND 41013 AT 12Z BOTH RPRTG
050/25 G 31 KT AT 12Z...BELIEVE MARGINAL GALES ARE PRESENT IN THE
GULF STREAM TO THEIR IMMED E OVER ZONE ANZ835. MAX SEAS OVER THE
SRN NT2 WTRS ARE IN THE 8-11 FT RANGE WHICH ARE RUNNING ON AVG 1-3
FT HIGHER THAN FCST BY THE 06Z WAVEWATCH III AND 00Z ECMWF
WAM...SO WL CONT TO ADJUST UP THE FCST SEAS ACRS THESE WTRS OVER
THE IMMED SHORT TERM.

OVER THE SHORT TERM...THE LATEST MDLS PRESENT NO MAJOR CHNGS TO
THEIR PREV FCST SCENARIOS OF FCSTG THE STRONG HIGH TO GRADLY
WEAKEN AS ITS BLDS TWD THE NRN MID ATLC COAST THRU TONITE...THEN
PASSES SE ACRS THE WTRS SUN INTO SUN NITE. PER THE 06Z NAM/GFS...
THE ONLY MINOR CHNG TO THE PREVLY USED WINDS FOR THE STRONG NELY
GRADIENT ACRS THE SRN NT2 WTRS WL BE TO EXTEND THE MARGINAL GALE
WRNG INTO EARLY THIS EVENING FOR ZONE ANZ835...BEFORE DMNSHG AS
PREVLY FCSTD LATER TONITE INTO SUN NITE. THEN SUN NITE INTO MON
NITE THE 06Z NAM/GFS CONFIRM THE TREND OF THE PREV 00Z MDLS IN
FCSTG A STRONG COLD FRONT TO PUSH SE ACRS THE WTRS WITH ASCD GALES
ACRS THE NRN WTRS. THEREFORE PLAN ON CONTG TO USE A MIX OF THE
00Z GFS 10M THEN 30M BL WINDS FOR THIS FROPA WITH JUST SM MINOR
TWEAKS IN DEFERENCE TO THE 06Z GFS AND 00Z ECMWF. SO OVERALL NO
MAJOR SHORT TERM CHNGS ARE PLANNED FOR THE NEXT OFSHR FCST
PACKAGE.

IN THE LONG RANGE...THE 00Z ECMWF SOLUTION STIL LOOKS LK A RSNBL
COMPROMISE BTWN THE STRONGER AND MR PROGRESSIVE 06Z/00Z GFS AND
THE WEAKER 00Z GEM/NAVGEM/UKMET SOLUTIONS FOR A STRONG WARM FRONT
LIFTING N ACRS THE WTRS TUE NITE/WED...FLWD BY A COLD FRONT MOVG
OFSHR WED NITE. SO AGAIN WL MAKE JUST SM MINOR ADDITIONAL EDITS TO
THE PREVLY USED 00Z ECMWF BL WINDS WHICH WL RESULT IN NO SIG CHNGS
TO THE PREV OFSHR FCSTS.


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


FOR THE SHORT TERM...LIGHT WINDS WILL CONT OVER THE NRN PORTION
OF THE WATERS AS LARGE SFC HIGH OVER THE MID CONTINENTAL UNITED
STATES MOVES E...AND OFFSHORE SUN. FOR THE STHRN WATERS...THE
STRONG HIGH WILL CREATE AN INCREASING NE TO E FLOW TODAY BEFORE
EASING TO ESE TNGT. S OF HATTERAS CANYON...WINDS WILL BE DRCTLY
OPPOSED TO THE GULF STREAM WITH MINIMAL GALES OCCURING S OF CAPE
FEAR OVER THE GULF STREAM FOR A PERIOD TODAY. THESE WINDS ARE NOT
RFLCTD IN THE GDNC...BUT THE MODELS DO NOT PICK UP ON GULF STREAM
EVENTS. WINDS WILL GRADU EASE TNGT AND SUN AS THE CNTR OF THE HIGH
PASSES TO THE N...THEN NE OF THIS AREA.

NEXT CONCERN IS COLD FRONT FCST TO MOVE OFFHSORE SUN NGT...THEN
FCST TO QUICKLY MOVE E OF THE WATERS MON. COMPARED WITH THE OTHER
MODELS...THE GFS LOOKS A LITTLE SLOW WITH THE SPEED OF THE NRN NRN
PART OF THE FRONT...BUT FASTER OVR THE SRN WATERS. THE ECMWF
AGREES WELL WITH UKMET/GEM/NAM AND WILL BE USED FM 06Z ONWARD...
BUT WILL BOST WINDS ABOUT 15 PCT...MINALY IN THE N TO NW FLOW. THE
GFS/ECMWF/UKMET AGREE ON SW GALES BTWN HTTRS CNYN AND S OF GEORGES
BANK MON...WITH POST FRONTAL GALES LIKELY OVER ALL WATERS N OF
HTTRS CANYON MON AFTN. THE NEXT LRG SFC HIGH WILL FOLLOW...AND IS
FCST TO SLIDE E OVR THE WATERS TUE.

THIRD EVENT IS COLD FRONT FCST TO MOVE E ACROSS THE WATERS WED.
FOR TUE NGT...MODELS QUICKLY VEER WINDS TO S TO SW AND INCRS TO
GALE FRC OVERNIGHT. BY 12Z WED...GFS/ECMWF/UKMET/GEM ALL FCST SW
GALES N OF BALT CNYN. THE GFS IS THE STRNGST AGAIN...AND LOOKS
OVERDONE IN THE SW FLOW N OF THE GULF STREAM WHERE THE LOWER LVLS
BCM STABLE. IF THE GFS 925 MB WIND FCST OF 80 KT IS CORRECT...
THEN THESE HIGHER WINDS WILL BE MORE LIKELY...BUT ATTM DO NOT BLV
SO. ALSO ON WED...THE MODELS BCN TO DIFFER SLGTLY. THE UKMET DVLPS
A STRNG WV ON THE WARM FRONT AND TAKES IT EASTWARD AND BCMS AN
OUTLIER. THE GFS TAKES A STRONG LOW NE ACRS SRN QUE WHILE THE
ECMWF/GEM AGREE ON A WEAKER FRONT AND ALSO AGREE ON PROGRESS OF
ASSD COLD FRONT. THE GFS RMNS A COMPARITIVELY TOO FAST AS BEFORE.
WILL USE ECMWF FOR GDNC FROM 12Z WED ON.

.SEAS...THE 00Z WAVEWATCH III HAS INITIALIZED FAIRLY WELL...EXCEPT
SEAS ARE 1 TO 3 FT UNDERDONE OVR THE FAR SRLY WATERS IN THE MOD NE
FLOW. THE ECMWF WAM HAS SLGTLY HIGHER SEAS AND POPULATE USING
USING A 50/50 BLEND OF THE WVWTCH AND WAM. BY 06Z SUN...WILL USE
100 PCT WAM AS THE ECMWF IS THE PREFERRED MODELS FOR SFC WINDS.


.EXTRATROPICAL STORM SURGE GUIDANCE...AS THE NE WINDS OVR THE SRN
WATERS INCRS...THE ESTOFS HAS A 1 TO 1.5 FT SURGE ALONMG THE GA
COAST THIS MRNG...THAT SPREADS NE TO THE NC COAST TODAY...THEN
GRADU DMNSHS SUN. THENA NEG SURGE OF 1 TO 1.5 FT IS FCST TO
DVLPMON OFF THE MID ATLC COAST AND GRADU EXPANDING ALOING MOST OF
TH COAST MON NGT IN THE NIOCRSNG OFFSHR FLOW..THE DMMSHS TUE.



.WARNINGS...PRELIMINARY.

.NT1 NEW ENGLAND WATERS...
.ANZ800...GULF OF MAINE...
     GALE POSSIBLE MON INTO MON NIGHT.
.ANZ805...GEORGES BANK WEST OF 68W...
     GALE POSSIBLE MON INTO MON NIGHT.
     GALE POSSIBLE WED INTO WED NIGHT.
.ANZ900...GEORGES BANK EAST OF 68W...
     GALE POSSIBLE MON INTO TUE.
     GALE POSSIBLE WED INTO WED NIGHT.
.ANZ810...SOUTH OF NEW ENGLAND...
     GALE POSSIBLE MON INTO MON NIGHT.
     GALE POSSIBLE WED NIGHT.
.ANZ815...SOUTH OF LONG ISLAND...
     GALE POSSIBLE MON.
     GALE POSSIBLE WED NIGHT.

.NT2 MID ATLC WATERS...
.ANZ820...HUDSON CANYON TO BALTIMORE CANYON...
     GALE POSSIBLE MON.
     GALE POSSIBLE WED NIGHT.
.ANZ915...HUDSON CANYON TO THE GREAT SOUTH CHANNEL...
     GALE POSSIBLE MON INTO MON NIGHT.
     GALE POSSIBLE WED INTO WED NIGHT.
.ANZ920...BALTIMORE CANYON TO THE GREAT SOUTH CHANNEL...
     GALE SUN NIGHT.
     GALE POSSIBLE MON.
     GALE POSSIBLE WED INTO WED NIGHT.
.ANZ905...THE GREAT SOUTH CHANNEL TO THE HAGUE LINE...
     GALE POSSIBLE MON INTO TUE.
     GALE POSSIBLE WED INTO WED NIGHT.
.ANZ910...EAST OF THE GREAT SOUTH CHANNEL AND SOUTH OF 39N...
     GALE POSSIBLE MON INTO MON NIGHT.
     GALE POSSIBLE WED INTO WED NIGHT.
.ANZ825...INNER WATERS FROM BALTIMORE CANYON TO CAPE CHARLES LIGHT...
     GALE POSSIBLE WED NIGHT.
.ANZ828...INNER WATERS FROM CAPE CHARLES LIGHT TO CURRITUCK BEACH LIGHT...
     GALE POSSIBLE WED INTO WED NIGHT.
.ANZ925...OUTER WATERS FROM BALTIMORE CANYON TO HATTERAS CANYON...
     GALE POSSIBLE MON.
     GALE POSSIBLE WED INTO WED NIGHT.
.ANZ830...INNER WATERS FROM CURRITUCK BEACH LIGHT TO CAPE HATTERAS...
     GALE POSSIBLE WED NIGHT.
.ANZ833...INNER WATERS FROM CAPE HATTERAS TO CAPE FEAR...
     GALE POSSIBLE WED NIGHT.
.ANZ930...OUTER WATERS FROM HATTERAS CANYON TO CAPE FEAR...
     GALE POSSIBLE WED NIGHT.
.ANZ835...INNER WATERS FROM CAPE FEAR TO 31N...
     GALE TODAY INTO TONIGHT.

$$

.FORECASTER VUKITS/PROSISE. OCEAN PREDICTION CENTER.



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