

033 

AGNT40 KWNM 172052

MIMATN



MARINE WEATHER DISCUSSION FOR N ATLANTIC OCEAN

NWS OCEAN PREDICTION CENTER WASHINGTON DC

452 PM EDT WED AUG 17 2016



.FORECAST DISCUSSION: MAJOR FEATURES/WINDS/SEAS/SIGNIFICANT

.WEATHER FOR THE NORTH ATLANTIC OCEAN W OF 50W FROM 30N TO 50N.



CRNT SFC RPRTS INDC SW WINDS UP TO 30 KT FM SHIPS OVR AND JUST E

OF GEORGES BANK JUST AHEAD OF AN APCHG CDFNT. THE ASCD SFC LOW IS

ANALYZED NEAR HALIFAX PER OPC 18Z SFC ANALYSIS. 15Z ASCAT-B PASS

RETURNED SW 15 TO 25 KT FM FAR NRN NT2 WTRS NWD WITH 30 KT AND

EVEN SOME 35 KT RETURNS JUST S OF NOVA SCOTIA AHEAD OF WARM FRONT

IN SLY FLOW. GOES SST SHOWED SOME HIGHER SST OF 22-23C IN THAT

AREA OF GALES...AND CONDITIONS MAY BE LESS STABLE IN THAT AREA.

WINDS DROP OFF TO 5 TO 15 KT IN CENTRAL AND SRN WTRS WHERE THERE

IS BROAD E-W RIDGE. 12Z GFS 10M WINDS APPEAR REPRESENTATIVE IN

OFSHR AND CSTL WTRS. THE 12Z GFS AND 12Z ECWMF/UKMET/GEM/NAM

AGREE WELL WITH THE TMG AND INTNSTY OF THE FRONT...AND INDC THE

LOW WL PULL THE FRONT S OF THE NT1 WTRS AND INTO THE NT2 WTRS INTO

TONIGHT. THE PREV FCST HAD WINDS TO 25 KT IN SE NT1 AND NE NT2

WTRS..AND THESE WINDS APPR IN LN WITH DATA.



OTRW...THE 12Z MDLS AGREE IN THE SHORT TERM...AND THE 12Z

GFS AND ECMWF ARE IN RSNBLY GOOD AGRMT THRUT THE REMAINDER OF THE

FCST PD...TAKING THE CURRENT BOUNDARY S INTO THE CENTRAL MT2 AREA

WHERE IT ATALLS LATE FRI AND FRI NIGHT. THE MDLS ALSO INDC

ANOTHER COLD FRONT WL PASS THRU NT1 WATERS THU NGT...THO THE WINDS

ARE XPCTD TO STAY WEAKER THAN THE CRNT FRONT BNDRY...AS THE UPPER

WINDS ARE NOT AS STG AS THOSE ASSOC WITH THE CRNT FRONT. THE 12Z

MDLS AGAIN INDC AN UPPER RDG WL BUILD OVER THE WRN ATLC FRI NGT

INTO SUN NGT...WHILE SOME WK SHRTWV ENERGY MOVS OFSHR E OF RDG THU

NIGHT INTO FRI. WHILE THERE HAVE BEEN A FEW SLIGHT DIFFS IN THE

ASCD SFC LOW(S) ALONG THE AFOREMENTIONED FRONTAL BNDRY AS IT SAGS

INTO NT2. HOWEVER...WINDS ARE XPCTD TO RMN LGT IN THE OFSHR

WATERS AND HAVE WINDS TO 25 KT CONFINED TO NE NT2 WTRS NR GLF

STREAM ASCD WITH ONE OF SFC LOWS CARRIED BY GFS/ECMWF THU NIGHT.

AS IN PREVIOUS FCST...FAVORED THE GFS...AND ATTM IT CONTINUES TO

BE WELL SUPPORTED BY THE REST OF THE 12Z GUID.



IN EXTENDED...FOR SAT NIGHT INTO SUN NIGHT A COLD FRONT APROACHES

MID ATLC COAST AND NEW ENGLAND FM W AND NW WHILE OLD STNRY FNTL

BNDRY SHIFTS N AHEAD OF THE CDFNT. THIS CDFNT THEN MOVS OFSHR MON

AND MON NIGHT. IN THE NLY FLOW BEHIND THE FNT USED A 50/50 BLEND

OF 12Z GFS 10M AND 30M WINDS FOR LATER MON AND MON NIGHT. THIS

WILL RESULT IN WINDS TO 25 KT FM SRN NT1 WTRS SWD WHERE SST'S ARE

HIGHEST.



.SEAS...BUOY REPORTS FM THE GULF OF MAINE AND GEORGES BANK INDC

SEAS TO 7 FT IN THE SW FLOW AHD OF THE APRCHG CD FRONT...HIGHEST

AT 44011. THE 12Z WNA NWW3 AND ECMWF WAM MDLS ARE INITALIZED WELL

WHEN COMPARED WITH THE 18Z SEA STATE ANALYSIS...AND CONTINUE THE

TREND WITH THE HIGHER SEAS MOVG OFF TO THE EAST WITH THE HIGHER

WINDS INTO TNGT. 12Z MDLS AGREE VERY WELL IN THE SHORT

TERM...THEN DIFFER SLIGHTLY IN THE EXTENDED PD. PLANNING ON USING

A 50/50 BLEND OF THE TWO MDLS AS A COMPROMISE SOLN.



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



.WARNINGS...PRELIMINARY.



.NT1 NEW ENGLAND WATERS...

     NONE.



.NT2 MID ATLC WATERS...

     NONE.



$$



.FORECASTER BANCROFT. OCEAN PREDICTION CENTER.

