Marine Interpretation Message
Issued by NWS

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000
AGNT40 KWNM 271405
MIMATN

MARINE WEATHER DISCUSSION FOR N ATLANTIC OCEAN
NWS OCEAN PREDICTION CENTER WASHINGTON DC
905 AM EST THU NOV 27 2014

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

AT 12Z...990 MB LOW IS OVR SRN NOVA SCOTIA AND MOVING NE AT 25
KT. LOW IS 5 MB DEEPER THEN THE 06Z GFS/NAM GUESS. ASSD COLD FRONT
EXTENDS S FM ERN NOVA SCOTIA TO NR 31N69W. WINDS HV DMNSHD ON THE
BACKSIDE OF THE LOW AS THE CRICLTN MVS NE. WHILE WINDS MAY BE
MARGINALLY GALE OVR THE ERN OFFSHOR WATERS BUT IN A FEW
HOURS..EXPECT SUSTAINED WINDS TO BE 32 KT OR LESS...SO WILL NOT
CONTINUE THE GALES OVER THE NRN WATERS. OFF THE SE COAST...W TO SW
WINDS ARE NOW BGGNG TO INCRS AS WEAK LOW INLAND MVS E TWDS THE NC
COAST. WL STAY WITH THE FCST MINIMAL GALES OVR THE SRN WATERS FOR
TODAY...DMNSHNG TNGT AS THE OW MVS OFF TO THE E. SEAS...OVER THE
GULF OF MAINE THIS MRNG ARE RUNNING 3 TO 5 FT...OR 20 TO 40 PCR
HIGHER THAN THE WAVE MODEL IN THE NW FLOW. OTW...SEAS ARE UNEVENLY
WITH A 1 OR 2 OF THE MODEL. WILL ADJUST THERE SEAS UPWARD FOR THE
FCST UPDATE...BUT OTW LTTL CHANGE.


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

AT 05Z SFC LOW WAS LOCATED ABOUT 60 NM OR SO E OF CAPE COD AND
HAS NOT APPEARED TO HAVE DEEPENED MUCH OVER PAST FEW HRS.
NUMEROUS BUOYS OVER GULF OF ME AND N OF CAPE COD BAY ARE
REPORTING SUSTAINED GALES. LIKE PREVIOUS FORECASTS WILL CARRY
GLWS INTO THE MORNING BUT ONLY OVER GLF OF ME ANZ800/GEORGES
BANK ANZ900 AND NERN MOST MID ATLC ANZ905 WATERS. 12Z MODELS
THEN INDICATE SFC LOW AND SECONDARY COLD FRONT WILL MOVE OFF THE
MID ATLC COAST THIS AFTERNOON IN RESPONSE TO MID/UPPER LVL
SHRTWV SWINGING SE AT BASE OF L/W TROF. 00Z GFS IS A BIT WEAKER
THAN PREVIOUS FEW RUNS WITH NW WINDS BEHIND COLD FRONT S OF CAPE
HATTERAS. STILL APPEARS THERE IS SOME POTENTIAL FOR GALES GIVEN
SHOT OF CAA BEHIND FRONT OVER 25 TO 27 DEG C SSTS. WITH GALES
ALREADY IN FORECAST WILL MAINTAIN CONTINUITY BUT WITH LESS
FORECAST CONFIDENCE. 00Z GFS IS THEN STRONGER WITH NEXT TRAILING
UPPER SHORTWV MOVING OFF NRN MID ATLC AND NEW ENGL EARLY FRI. IN
FACT 00Z GFS IS NOW INDICATING SFC LOW DVLPMNT AND ASSOCIATED
GALE FORCE BOUNDARY LAYER WINDS SE OF NANTUCKET FRI AFTERNOON
INTO FRI EVENING. PREVIOUS GRIDS WHICH WERE GFS/NAM BLEND LOOK
REASONABLE FRI AND FRI NIGHT WITH NW WINDS UP TO 25 KT OR 30 KT
EXPANDING N OVER NRN MID ATLC AND NEW ENGL WATERS.

00Z MODELS ARE IN GOOD AGREEMENT THAT HIGH PRES RIDGE WILL BUILD
TO MID ATLC AND NEW ENGL COASTS FRI NIGHT. 00Z GFS/GFSP/UKMET
AND 12Z/26 ECMWF ARE ALL IN PRETTY GOOD AGREEMENT THAT AS RIDGE
SHIFTS JUST E AND SE OF OFFSHORE WATERS SAT NIGHT THAT RETURN
FLOW WILL THEN BEGIN TO INCREASE SUN AND SUN NIGHT. AGAIN
PREVIOUS GRIDS LOOK ON TARGET IN INDICATING WINDS UP TO 20 OR 25
KT N OF HATTERAS CNYN. FOR WINDS BEHIND COLD FRONT USED A 2:1
BLEND OF 00Z GFS AND 12Z/26 ECMWF WHICH RESULTED IN MAX WINDS OF
25 KT.

SHORTLY AFTER 00Z BUOY 44066 REPORTED SIG WV HGT AS HIGH AS 19
FT WHICH WAS NEARLY DOUBLE THE 00Z MWW3. THESE HIGHER SIG WV
HGTS HAVE SINCE SHIFTED E INTO OUTER DATA VOID OFFSHORE WATERS.
WILL BUMP UP SIG WV HGTS A FT OR TWO OVER 00Z MWW3 S OF CAPE
HATTERAS TODAY AND TONIGHT TO ACCOUNT FOR WINDS BEING SLIGHTLY
HIGHER 00Z GFS 10M. THEN LIKE WINDS WILL USE 1:1 BLEND OF 00Z
MWW3 AND 12Z/26 ECMWF THROUGH REMAINDER OF FORECAST PERIOD.

.EXTRATROPICAL STORM SURGE GUIDANCE...WATER LVL ANOMALIES AT
NANTUCKET AND WOODS HOLE WHEN SURGE GUIDANCE IS TAKEN INTO
ACCOUNT HAVE BEEN IN +0.5 TO 1.0 FT OVER PAST FEW HOURS. AS
WINDS SHIFT TO OFFSHORE 00Z ESTOFS INDICATED NEGATIVE SURGE
AROUND 1 FT FROM NJ TO COASTAL ME THIS AFTERNOON AND -1 TO -2 FT
ALNG COAST S OF CAPE LOOKOUT WITH OFFSHORE GALES. 00Z ETSS IS
CLOSER TO ZERO IN BOTH THESE AREASWITH  A COMPROMISE LIKELY THE
MOST REASONABLE.


.WARNINGS...PRELIMINARY.

.NT1 NEW ENGLAND WATERS...
     NONE.

.NT2 MID ATLC WATERS...
.ANZ833...INNER WATERS FROM CAPE HATTERAS TO CAPE FEAR...
     GALE TODAY INTO TONIGHT.
.ANZ930...OUTER WATERS FROM HATTERAS CANYON TO CAPE FEAR...
     GALE TODAY INTO TONIGHT.
.ANZ835...INNER WATERS FROM CAPE FEAR TO 31N...
     GALE TODAY INTO TONIGHT.
.ANZ935...OUTER WATERS FROM CAPE FEAR TO 31N...
     GALE TODAY.

$$

.FORECASTER PROSISE/CLARK. OCEAN PREDICTION CENTER.



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