

482 

AGNT40 KWNM 150703

MIMATN



MARINE WEATHER DISCUSSION FOR N ATLANTIC OCEAN

NWS OCEAN PREDICTION CENTER WASHINGTON DC

303 AM EDT MON AUG 15 2016



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

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



SHORT TERM SUMMARY...1013 MB LOW PRES OVR THE GULF OF MAINE EARLY

THIS MORNING IS MOVG E. AN ASSOC COLD FRONT EXTENDS SW FROM THE

LOW TO NR CAPE COD...AND THEN FURTHER SW TOWARD LONG ISLAND PER

THE 06Z PRELIM OPC-NCEP SFC ANALYSIS. THE LOW WILL MOVE E OF THE

WTRS TODAY AS THE FRONT SLIDES SE OVR THE REMAINING NT1

WTRS...STALLS THE FAR NRN NT2 WTRS OR NR 39N TONITE INTO

TUE...THEN RETURNS N OVR NT1 WTRS AS A WARM FRONT LATER TUE INTO

TUE NITE AS THE NEXT LOW PRES AREA SLIDES E FROM THE GREAT LAKES.

THIS LOW WILL TRACK E OVR THE GULF OF MAINE WED...WITH AN ASSOC

COLD FRONT TRAILING SW FROM THE LOW. THE LOW WILL MOVE E OF THE

OFF WTRS WED NITE WITH THE FRONT EXTENDING SW FROM THE LOW INTO

NRN NT2 WTRS OR ROUGHLY ALONG 39-40N. WEAK HIGH PRES AREAS WILL

FOLLOW EACH COLD FRONT...AND MOVE OVR PORTIONS OF THE NT1 WTRS

TONITE INTO TUE...AND AGAIN WED NITE. OTW...AN UPR LVL AND SFC

HIGH PRES RIDGE EXTENDING E FROM THE SRN AND CENTRAL NT2 WTRS WILL

PREVAIL THRU WED NITE. THE BEST CHANCE FOR SHWRS AND TSTMS WILL

BE NR EACH FRONTAL SYSTEM OVR THE NEXT FEW DAYS...AND ALSO OVR

FAR SRN NT2 WTRS WHERE TROPICAL MOISTURE SLIDES NW FROM THE

BAHAMAS. THE LATEST SATELLITE IMGRY AND LIGHTNING DENSITY DATA

INDICATES ONLY A FEW ISOLATED TSTMS OVR FAR SRN NT2 WTRS MOVING

OFF TO THE W AND NW AT THIS TIME. LOCALLY VERY GUSTY WINDS AND

ROUGH SEAS WILL BE FOUND IN OR NEAR ANY HEAVY TSTMS THAT FORM OVR

THE OFF WTRS DURING THE NEXT COUPLE OF DAYS.



SHORT TERM MODELS...FOR THE EARLY AM FCST PACKAGE...THE 00Z GLBL

MDLS ARE IN BETTER AGREEMENT OVR THE WTRS THRU WED NITE...WITH

THE LATE EVE ASCAT PASS IN GOOD AGREEMENT WITH THE 00Z GFS 10M

WINDS OVR THE REGION. AS A RESULT...WE WILL REMAIN CLOSE TO THE

00Z GFS 10M WINDS THRU WED NITE OVR THE WTRS...EXCEPT TO REDUCE

WINDS BY 5 PERCENT OVR THE COOLER SSTS N OF THE GULF STREAM...OR

ROUGHLY NT1 AND NRN NT2 WTRS...TUE NITE INTO WED NITE. WILL SERVE

TO ALIGN OUR GRIDS AND FCST A LITTLE BETTER WITH THE NEARBY

COASTAL WTRS FCSTS OFF THE NEW ENGLAND AND NRN MID ATLC COAST OVR

THE NEXT FEW DAYS.



LONG TERM SUMMARY AND MODELS...THE 00Z GLBL MDLS BEGIN TO DIVERGE

SOMEWHAT FOR THU AND BEYOND OVR THE WTRS. THE 00Z ECMWF APPEARS

TO BE THE MOST CONSISTENT THU THRU FRI NITE OVR THE REGION. FOR

THE EARLY AM FCST WE WILL USE A 50-50 BLEND OF THE 00Z ECMWF

AND...PREV FCST...OR 12Z ECMWF FROM YESTERDAY. THIS WILL RESULT IN

LITTLE CHANGE FROM THE PREV FCST FOR THE EARLY AM PACKAGE. A

FRONT WILL BECOME NEARLY STNRY ALONG 39-40N THU AND WEAKEN...WITH

THE HIGH PRES RIDGE PERSISTING OVR SRN AND CENTRAL NT2 WTRS. THE

NEXT COLD FRONT WILL APPROACH THE NT1 WTRS FROM THE NW EARLY THU

NITE...THEN CROSS THE NT1 WTRS LTR THU NITE AND EARLY FRI...

REACHING NRN NT2 WTR DURING THE DAY FRI INTO FRI NITE AS THE HIGH

OVR THE SRN NT2 WTRS FINALLY WEAKENS. NO HEADLINES APPEAR LKLY

THRU THE FCST...WITH CONFDC LVLS NR TO ABOVE AVERAGE.



SEAS...THE 06Z RA1 SEA STATE ANALYSIS INDICATES SEA HEIGHTS RANGING

FROM 2 TO 5 FT OVR THE OFF WTRS...WITH THE HIGHEST SEA HTS OVR

NRN NT2 WTRS. THESE SEA HEIGHTS ARE RUNNING WITHIN A FT OR SO

OFTHE 00Z WNA WAVE WATCH III MDL OUTPUT. FOR THE EARLY AM PACKAGE

WE WILL REMAIN CLOSE TO THE WW3 MDL GUID INTO WED NITE...AND THEN

TRANSITION TOWARD A 50-50 BLEND OF THE PREV FCST AND 00Z ECMWF

WAM MDL GUID WHICH WILL PRETTY MUCH ALIGN THE SEA HEIGHTS FCST TO

THE WIND FCST AS DESCRIBED ABOVE.



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



.WARNINGS...PRELIMINARY.



.NT1 NEW ENGLAND WATERS...

     NONE.



.NT2 MID ATLC WATERS...

     NONE.



$$



.FORECASTER MILLS. OCEAN PREDICTION CENTER.

