Marine Interpretation Message
Issued by NWS

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AGNT40 KWNM 031307
MIMATN

MARINE WEATHER DISCUSSION FOR N ATLANTIC OCEAN
NWS OCEAN PREDICTION CENTER WASHINGTON DC
907 AM EDT FRI JUL 3 2015

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

THE GOES IR/VIS IMGRY INDC A FRNTL SYS ACRS THE W ATLC...WITH A
BAROCLINIC LEAF INVOF NOVA SCOTIA...INDCG A WAVE ALNG THE
FRNT...CRNTLY CTRD S OF NOVA SCOTIA. THE 06Z GFS INDC A FEW GALES
AHD OF THE FRNT NR THE LOW CTR...AND INDC THE GALES WL CONT EARLY
TDA BTWN THE FRNT AND HIGH PRES TO THE SE. THE 00Z ECWMF IS NOT
QUITE AS STG...BUT IS NRMLLY A LTL CNSRVTV...AND INDC ABT 30 KT.
FOR NOW PLANNING ON KEEPING GALES E OF OFSHR WTRS FOR EARLY
TDA...AS CONFDC IS ABT MDT TO HIGH WITH THEM...AS SFC OBS SPRT
THEM. ALSO...CRNT LGTNG DENSITY PROD INDC SHOWERS AND TSTMS ALNG
THE BNDRY...WITH THE FRNTL FRCG...MAINLY OVR THE LESS STABLE
ENVRMT OVR THE GLF STRM. THE PREV FCST HAD SCTRD SHOWERS AND
TSTMS...SO PLANNING ON KEEPING THEM IN THE UPDATE PKG.

OTRW...THE 06Z GFS RMNS IN RSNBLY GUD AGRMT THRUT THE PD WITH THE
00Z ECMWF SOLN...AND INDC THE FRONT WL STALL OVR THE AREA AND
PERSIST OVR NT2 INTO MON. THE MDLS ALL INDC A SHRTWV TROF WL MOV
THRU THE AREA ON SUN INTO MON...DVLP ANTHR WAVE ALNG THE
FRONT...WHICH PULLS IT TO THE E. THE GFS ALSO INDC THE CRNT RDG
NR 50W WL MOV E INADVOF THE SHRTWV...BEFORE ANTHR UPR RDG BLDS OVR
THE WATLC TUE INTO WED. THE 00Z GFS AGREES WELL WITH THE 00Z ECMWF
ON THE SEQUENCE OF EVENTS...AND HAS TRENDED TWD THE ECWMF FM THE
00Z SOLN WITH THE DVLPMT OF ANTHR WK LOW ALONG THE TAIL END OF
THE AFOREMENTIONED FRONT OVR NT2. THE PREV RUNS HAD THE LOW JUST
OFSHR...BUT NOW INDC IT WL RMN JUST INLND...JUST LIKE THE ECMWF.
THE PREV FCST FAVORED THE ECMWF IN THE EXTENDED...SO WL STAY ALONG
THOSE LINES IN THE UPDATE PKG.

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

06Z NCEP SFC ANAL HAS A MAIN FNTL BNDRY ACRS THE SE NT1 WTRS SW TO
NE NC CONTAINING A FNTL WAVE NR 40N69W. REMAINS OF WEAKER FNTL
BNDRY ALONG OUTER NT2 WTRS APPRS MARKED BY SCT TSTMS. LTG DENSITY
PROD SHOWS CONVECTION MOST PREVALENT AND HEAVIER WITH OLD BNDRY
AND GLF STREAM. ARE CARRYING WX IN FORM OF SCT SHWRS AND TSTMS
NRN AND CENTRAL NT2 WTRS AND MAINLY SHWRS SRN NT1 WHERE LTG
DENSITY SHOWS LTL ACTVTY.

LATEST MDLS APPR WELL INITIALIZED AND PICK UP ON WAVE MOVG ALG FNT
ACRS NRN NT2 SLIDING NE NR 1000 FM AND A SOMEWHAT STRONGER FNTL
WAVE EXPECTED SAT ALSO IN MDLS. BIGGEST THREAT FOR GALES IS WITH
PRESENT WAVE NE NT2 WTRS SUCH AS 910 ALG GLF STRM AND SECOND WAVE
ON S SIDE WHERE 12Z ECMWF/UKMET SHOW SOME 30 KT 10M WNDS DURING
ITS PASSAGE BUT THE USUALLY MORE ROBUST CNDN IS NOT THAT
IMPRESSIVE AND GFS PEAKS AT 30 KT BUT FOR ITS HIGHER 30M WNDS
WHICH APPR BEST REPRESENTATIVE ALG/S OF GLF STRM. AFTER 12Z SUN
GOING MORE WITH 00Z ECMWF WITH GFS DEPARTING FM OTHER MDLS WITH
MORE NRN TRACK OF WEEKEND WAVE. OVERALL MDL AGRMT IS GOOD THRFTR
BUT STAYING WITH ECMWF. FOR WRNGS USING 30M GFS WNDS AND ALSO
BOOSTING ECMWF WNDS ALG GLF STRM GIVES GALES IN ANZ910 AND SINCE
GLF STRM IS THER WILL GO WITH NEAR TERM GALE TODAY WITH LOW TO MDT
CONFDC AND THER ARE ALSO TSTMS IN AREA.

 SEAS...THE 00Z WNA WW3 AND ECMWF WAM BOTH INDICATE SEAS TO 10 FT
OR SO OUTER NT2 WTRS ASCD WITH FIRST WAVE WITH SOME DIFFERENCES
DVLPG SAT WITH STRONGER FNTL WAVE WITH DIFFERENCES MAINLY OVR NT2
WTRS. SIDING WITH ALL WMA WW3 TODAY AND THEN TONIGHT TRANSITIONING
OVR TO 50/50 MDL BLEND.

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


.WARNINGS...PRELIMINARY.

.NT1 NEW ENGLAND WATERS...
     NONE.

.NT2 MID ATLC WATERS...
.ANZ910...EAST OF THE GREAT SOUTH CHANNEL AND SOUTH OF 39N...
     GALE TODAY.

$$

.FORECASTER KELLS/BANCROFT. OCEAN PREDICTION CENTER.



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