Marine Interpretation Message
Issued by NWS

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AGNT40 KWNM 312001
MIMATN

MARINE WEATHER DISCUSSION FOR N ATLANTIC OCEAN
NWS OCEAN PREDICTION CENTER WASHINGTON DC
401 PM EDT TUE MAY 31 2016

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

THE ASCAT PASS FROM 15Z INDICATES MAINLY LESS THAN 20 KT ACROSS
THE OFFSHORE WATERS...THE EXCEPTION IS 25-30 KT OCCURING VCNTY OF
THE GULF STREAM ACROSS N CENTRAL MID ATLANTIC WATERS. THE REMNANTS
OF BONNIE AS SHOWN BY SAT PIX AND CURRENT OBS APPEAR TO REMAIN OFF
THE N ERN CST OF SOUTH CAROLINA AND NEARLY STATIONARY. SEAS ARE
GENERALLY RUNNING 3-7 FT ACROSS OFFSHORE WATERS.

FOR THE MOST PART THE 12Z GLOBAL MODELS ARE IN PRETTY GOOD
AGREEMENT THROUGHOUT THE 7 DAY PERIOD. THE REMNANTS OF BONNIE WILL
TRACK VERY SLOWLY NE ACROSS THE WATERS DURING THE NEXT 5 DAYS.
WED INTO FRI A HIGH PRES RIDGE WILL BUILD ACROSS MUCH OF THE NEW
ENGLAND WATERS AS WINDS TURN E-NE. A COLD FRONT WILL APPROACH THE
ERN SEABOARD ON DAY 5 AS WINDS SHIFT TO SW INADV OF BNDRY AND
INCREASE TO 20-30 KT. ATTM I AM NOT FORECASTING ANY GALES TO
OCCUR...ALTHOUGH A SMALL POSS REMAINS...ESPECIALLY S OF THE GULF
STREAM. WILL POP THE WIND GRDIS USING THE GFS THROUGHOUT...WITH
SMALL EDITS TO INCREASE WINDS AS NEEDED.

WAVES...BOTH THE WNA AND WAM INITIALIZED WELL AND ARE VERY SIMILAR
THROUGHOUT THE 7 DAY PERIOD. WILL POP THE SEAS USING A 50/50 BLEND
OF THE TWO WAVE MODELS.

LATEST OBS AGREE WELL WITH CURRENT GRIDS. ATTM I DONT PLAN ON
MAKING ANY CHANGES TO CURRENT GRIDS OR ASSOCIATED TEXT FCST.

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

GOES IR IMGRY INDC POST-TROPICAL BONNIE HAS MOVED OFF THE COAST OF
SOUTH CAROLINA OVER THE PAST SEVL HOURS...AND CRNT SFC RPRTS INDC
ALSO INDC THE CIRCULATION CENTER HAS MOVED OFFSHORE. ASCAT DATA FM
0246 UTC INDC UP TO 25 KT E OF THE LOW...NR THE UNSTABLE
ENVIRONMENT OVER THE GULF STREAM. IN ADDITION...CRNT LGTNG DATA
AND THE ERN EDGE OF THE RADAR SHOW CONVECTION STARTING TO DVLP
S OF THE LOW CENTER...AND MAY INDC TPRCL CHARACTERISTICS COULD BE
DVLPG AGAIN...ALBEIT IN A LIMITED FASHION. THE 00Z
GFS/ECWMF/UKMET/GEM ALL INDC THE LOW WL DRIFT ALONG THE CAROLINA
COAST OVER THE NEXT 48 HOURS...AND THE GFS/UKMET AGREE WELL WITH
MOVING IT NE AFTERWARDS...THRU NRN NT2 ALONG A FRONTAL BNDRY. THE
GFS SLOWED SOME FROM THE 18Z RUN...BUT SEEMS RSNBL WITH THE
SRN EXTENT OF A UPR TROF MOVING IN FROM THE W SLOWLY STEERING IT
TO THE NE. HOWEVER...THE 00Z ECWMF/GEM ALSO AGREE...BUT KEEP THE
LOW ALONG THE SC COAST...BEFORE WKNG IT TO A TROF ON SAT. THE
PREV FCST FAVORED THE GFS IDEA...AND THE 00Z RUNS SEEMS TO BE A
DECENT CMPRMS AS IT SLOWS THE TRACK OF PT BONNIE...SO PLANNNING ON
FLWG FOR THIS SYSTEM. ALSO...PLANNING ON BOOSTING WINDS SLIGHTLY
NR THE LOW...AS THE GFS WAS INITIALIZED A TAD LOW WHEN COMPARED
WITH THE DATA.

OTRW...THE CRNT GOES WV IMGRY INDC AN UPR RDG OVR THE WRN
ATLC EXTENDING INTO NE NT2...AND A WK SHORTWAVE TROF MOVING
THROUGH SE CANADA TWD THE COAST. THE LTST NCEP SFC ANALYS INDC A
CDFNT JUST ABT TO THE NEW ENGLAND COAST...ASSOC WITH THE
AFOREMENTIONED SHORTWAVE. THE 00Z MDLS ALL INDC WK FRNTL BNDRY WL
MOVE OVER NT1 TDA AND QUICKLY WKN...FLWD BY A SECOND WK SYSTEM
TNGT INTO WED. THE 00Z GFS/ECWMF ARE IN RELATIVELY GUD AGRMT ON
THE TMG OF THESE SYSTEMS...AND THE GFS HAS CONSISTENLY INDC WINDS
TO 25 KT IN THE SW FLOW AHEAD OF THE FIRST BNDRY TDA. THIS SEEMS
OVERDONE SLIGHTLY...ESP OVER THE STABLE ENVIRONMENT OVER THE COLD
SHELF WATERS...SO PLANNING ON CAPPING WINDS AT 20 KT.

IN THE EXTENDED PERIOD...PT BONNIE IS EXPECTED TO MOVE SLOWLY E
THROUGH THE NRN NT2 WATERS THU INTO FRI ALONG THE AFOREMENTIONED
WEAK SECOND FRONTAL BNDRY...AS HIGH PRES BUILDS OVER NT2 BEHIND
IT. THE 00Z GFS INDC ANOTHER VERY WEAK SYSTEM WL MOVE INTO NT1
SAT...HAS NOT CHANGED MUCH FROM EARLIER RUNS...AND IS SOMEWHAT
CLOASE TO THE 12Z ECMWF. HOWEVER...THE 00Z ECMWF/UKMET SOLNS ARE
A BIT SLOWER WITH THE BNDRY...AND WKN IT FASTER. ATTM UNCERTAINTY
IS FAIRLY HIGH...SO PLANNING ON STAYING WITH THE 00Z GFS FOR THE
FCST...WHICH KEEPS IT CLOSE TO CONTINUITY.

SEAS...THE 00Z WAVEWATCH III AND 12Z ECWMF WAM MDLS HAVE BOTH
INITIALIZED THE WV HTS RSNBL WELL. ATTM PLANNING ON STAYING CLOSE
TO THE 00Z WW3...WHICH REFLECTS PREFERRED 00Z GFS WX MDL TRENDS.
HOWEVER...PLANNING ON BOOSTING SEAS NEAR PT BONNIE SLIGHTLY...TO
ACCT FOR CRNT CNVCTV ACTIVITY DVLPG NEAR THE LOW.

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



.WARNINGS...PRELIMINARY.

.NT1 NEW ENGLAND WATERS...
     NONE.

.NT2 MID ATLC WATERS...
     NONE.

$$

.FORECASTER SHAW. OCEAN PREDICTION CENTER.



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