

711 

AGNT40 KWNM 030925

MIMATN



MARINE WEATHER DISCUSSION FOR N ATLANTIC OCEAN

NWS OCEAN PREDICTION CENTER WASHINGTON DC

525 AM EDT SAT SEP 3 2016



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

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



THE LATEST SAT IMG INDC A WEAK RIDGE ACROSS THE NRN WATERS WITH

TROPICAL CYCLONE HERMINE ABOUT TO ENTER THE WATERS NEAR VA COAST.

BUOY 41004 SE OF CHARLESTON SC EARLIER HAD WINDS 40 KT WITH GUSTS

TO 55 KT AT 22Z WITH 19 FT SEAS. BUOY 44064 FIRST LANDING VA HAS

WINDS INCREASING NOW AT 30 KT AND GUSTS TO 40 KT WITH 7 FT SEAS

WHILE CBBV2 CHESAPEAK BAY BRIDGE TUNNEL VA HAS REPORTS AT 10M

WINDS 35 KT WITH GUSTS TO 40 KT . ALL THE LATEST OBS INCLUDING

ASCAT PASS NOW SHOW HIGHER WINDS OVER THE WRN PARTS OF THE CENTRAL

REGION. AT 0600Z THE NCEP MAP HAS HERMINE OVER VA WHILE A WEAK

STATIONARY FRONT LIES ACROSS THE CENTRAL WATERS. THE PRES GRADIENT

IS STILL FAIRLY RELAXED OVER THE WATERS N OF THE FRONT AND STILL

VERY TIGHT OF COURSE OVER THE CENTRAL REGION.



THE GLOBAL MODELS HAVE INITIALIZED WELL THE 06Z OBSERVATIONS WITH

JUST MINOR DIFFERENCES IN WIND SPEEDS OVER THE CENTRAL WATERS. THE

MODELS STILL HAVE SOME DIFFERENCES IN THE SHORT TERM REGARDING THE

TRACK OF HERMINE AND THESE DIFFERENCES HAVE INCREASED WITH TIME.

THE MODELS DIVERGE MOSTLY IN THE EXTENDED PERIOD. GFS WILL STAY

WITH THE OFFICIAL TRACK AND WILL USE BOTH GFS AND THE ECMWFHR TO

ADJUST WINDS ACCORDINGLY. I PLAN ON NOT MAKING ANY MAJOR CHANGES

TO THE REST OF THE FORECAST WATERS AND SO WILL USE THE FRCST WINDS

AND RETAIN MOST OF THE FORECAST. IN THE SHORT TERM THE CENTRAL AND

SRN WATERS WILL CONTINUE TO BE HEAVILY IMPACTED BY HERMINE WHILE A

RIDGE WILL PERSIST OVER THE NRN WATERS.



.SEAS...THE NCEP MAP FOR WAVEHEIGHTS AT 06Z HAD HIGHER SEAS WITH

PEAKS TO 23 FT OVER WATERS ADJACENT TO VA COAST. SEAS ARE LESS

THAN 8 FT OVER THE NRN WATERS WITH MAINE STILL HAVING SEAS BETWEEN

2 AND 4 FT. THE NWW3 WAVE MODEL STILL FITS VERY WELL WITH THE

OBSVERVED SEAS PATTERN AND MATCHES THE PEAK VALUE OVER THE CENTRAL

WATERS. NWW3 IS STILL VERY CLOSE TO THE ECMWFWAVE AND BOTH WAVE

MODELS HAVE BECOME BETTER AT MATCHING THE PEAK SEAS. WILL CONTINUE

WITH NWW3 FOR SEAS. IN THE SHORT TERM SEAS WILL REMAIN LEVATED

OVER THE CENTRAL WATERS BUT WILL START TO SUBSIDE IN THE EXTENDED

PERIOD.



.EXTRATROPICAL STORM SURGE GUIDANCE...WITH MOST OF THE MODELS

FCSTG HERMINE TO SLOW AND NEARLY STALL OFF THE NRN MID ATLC AND

SRN NEW ENGLAND COASTS SUN INTO TUE...THERE IS A HIGH LIKELIHOOD

OF SIGNIFICANT AND POSSIBLY LIFE THREATENING FROM THE DELMARVA

PENINSULA TO THE SOUTHERN NEW ENGLAND COAST LATE TODAY POSSIBLY

THROUGH MIDWEEK NEXT WEEK. FOR FURTHER DETAILS AND GUIDANCE PLEASE

SEE THE STORM SURGE SECTION OF THE NHC PUBLIC ADVISORY AND THE NHC

PROTOTYPE STORM SURGE WATCH/WARNING GRAPHIC AT:

WWW.HURRICANES.GOV/GRAPHICS_AT4.SHTML?WSURGE (ALL LOWERCASE).



NHC KEY MESSAGE:



1. HERMINE IS EXPECTED TO BECOME A POST-TROPICAL CYCLONE WHILE

STILL PRODUCING HAZARDOUS WINDS AND STORM SURGE OVER LAND. NWS

POLICY ALLOWS NHC TO WRITE ADVISORIES ON AND ISSUE TROPICAL STORM

WATCHES AND WARNINGS FOR POST-TROPICAL CYCLONES, WHEN THE SYSTEM

CONTINUES TO POSE A SIGNIFICANT THREAT TO LIFE AND PROPERTY. NHC

AND THE NWS EASTERN REGION HAVE DECIDED THAT THIS OPTION WILL BE

INVOKED FOR HERMINE. AFTER HERMINE BECOMES A POST-TROPICAL

CYCLONE, NHC WILL CONTINUE TO ISSUE ITS FULL SUITE OF ADVISORY AND

WARNING PRODUCTS FOR AS LONG AS THE SYSTEM REMAINS A SIGNIFICANT

THREAT TO LAND.



.WARNINGS...PRELIMINARY.



.NT1 NEW ENGLAND WATERS...

.ANZ805...GEORGES BANK WEST OF 68W...

     TROPICAL STORM POSSIBLE WED INTO WED NIGHT. 

.ANZ810...SOUTH OF NEW ENGLAND...

     TROPICAL STORM TONIGHT INTO SUN NIGHT. 

     TROPICAL STORM POSSIBLE MON INTO WED NIGHT. 

.ANZ815...SOUTH OF LONG ISLAND...

     TROPICAL STORM TONIGHT INTO SUN NIGHT. 

     TROPICAL STORM POSSIBLE MON.

     HURRICANE POSSIBLE MON NIGHT.

     TROPICAL STORM POSSIBLE TUE INTO WED NIGHT. 



.NT2 MID ATLC WATERS...

.ANZ820...HUDSON CANYON TO BALTIMORE CANYON...

     TROPICAL STORM TODAY INTO SUN NIGHT. 

     TROPICAL STORM POSSIBLE MON.

     HURRICANE POSSIBLE MON NIGHT.

     TROPICAL STORM POSSIBLE TUE INTO WED. 

.ANZ915...HUDSON CANYON TO THE GREAT SOUTH CHANNEL...

     TROPICAL STORM TODAY INTO SUN NIGHT. 

     TROPICAL STORM POSSIBLE MON.

     HURRICANE POSSIBLE MON NIGHT.

     TROPICAL STORM POSSIBLE TUE INTO WED NIGHT. 

.ANZ920...BALTIMORE CANYON TO THE GREAT SOUTH CHANNEL...

     TROPICAL STORM TODAY INTO SUN NIGHT. 

     TROPICAL STORM POSSIBLE MON.

     HURRICANE POSSIBLE MON NIGHT.

     TROPICAL STORM POSSIBLE TUE INTO WED. 

.ANZ905...THE GREAT SOUTH CHANNEL TO THE HAGUE LINE...

     TROPICAL STORM POSSIBLE WED INTO WED NIGHT. 

.ANZ825...INNER WATERS FROM BALTIMORE CANYON TO CAPE CHARLES LIGHT...

     TROPICAL STORM EARLY TODAY INTO SUN NIGHT. 

     TROPICAL STORM POSSIBLE MON INTO TUE. 

.ANZ828...INNER WATERS FROM CAPE CHARLES LIGHT TO CURRITUCK BEACH LIGHT...

     TROPICAL STORM EARLY TODAY INTO SUN NIGHT. 

.ANZ925...OUTER WATERS FROM BALTIMORE CANYON TO HATTERAS CANYON...

     TROPICAL STORM TODAY INTO SUN NIGHT. 

     TROPICAL STORM POSSIBLE MON INTO TUE. 

.ANZ830...INNER WATERS FROM CURRITUCK BEACH LIGHT TO CAPE HATTERAS...

     TROPICAL STORM EARLY TODAY INTO TONIGHT. 

.ANZ833...INNER WATERS FROM CAPE HATTERAS TO CAPE FEAR...

 TROPICAL STORM TODAY.

.ANZ930...OUTER WATERS FROM HATTERAS CANYON TO CAPE FEAR...

     TROPICAL STORM EARLY TODAY INTO TONIGHT. 



$$



.FORECASTER MUSONDA/MUSONDA. OCEAN PREDICTION CENTER.

