Marine Interpretation Message
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204
AGNT40 KWNM 070217
MIMATN

MARINE WEATHER DISCUSSION FOR N ATLANTIC OCEAN
NWS OCEAN PREDICTION CENTER WASHINGTON DC
917 PM EST SAT FEB 6 2016

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

THE SAT IMG SHOW INCRSNG CONV OVR THE SRN WTRS FROM THE SW BUT
ALMOST NO LGHTNG STRIKES YET. THE RADAR INDC TSTMS CELLS
APPROACHING THE SRN WTRS FROM THE S. THE SREF HAS 20 PERCENT CHNCE
OF TSTMS OVR THE FAR SRN WTRS AND THAT CHNSCE WILL INCRS TO 40
PERCENT SUN AND WILL XTND TO THE CNTRL WTRS MON. AT 00Z HGH PRES
1028 MB OVR BALT CANYN HAS A RIDGE OVR THE NRN AND CNTRL WTRS
WHILE PRES FALLS DOMINATE THE SRN WTRS INDC FORMATION OF THE
ANTICIPATED LOW PRES THAT WILL DVLP SWIFTLY AND RESULT IN HURCN
FORCE WINDS OVR THE FAR SRN WTRS. THE PRES GRDNT IS VERY RELAXED
ATTM ACRS THE REGION AND THE MAX OBS WINDS ARE 25 KT OVR THE FAR
SW TIP OF THE REGION. THE LAST ASCAT PASS AT 1535Z INDCTD HGHR
WINDS OVR THE SW PARTS OF THE WTRS. THE HGST SEAS ARE OVR THE ERN
PARTS AND THEY RANGE BTWN 6 AND 9 FT WHILE THE WRN PARTS HVE SEAS
RANGING BTWN 3 AND 6 FT. THE NWW3 MULRI GRID WV MDL HAS A VERY
SIMILAR PATTERN TO THE OBSVD SEAS AND MATCHES THE PEAK VALUES VERY
WELL ACRS THE REGION BUT BECOMES UNDER DONE BY 3 FT OVR THE HS
WTRS NR NOVA SCOTIA AND ALSO IN THE AREA WITH HGHR WINDS NR
GREENLAND.

THE MDLS HAVE INITAILIZED WELL WITH THE OBS AND THEY HAVE DECENT
AGRMNT IN THE SHORT TERM ON THE LOW PRES THAT WILL PASS THRU THE
SRN AND CNTRL WTRS. JUST MNR DIFFS IN THE XTNDD PRD ON THE
STRENGTH OF THE WINDS AS A FRNTL BNDRY PASSES THE WTRS. WILL NOT
MAKE ANY MJR CHNGES TO THE CURR FORECAST AND WIL STICK TO GFS. IN
THE SHORT TERM THE HGH PRES OVR BALT CNYN WILL ZOOM NE AND ALLOW A
LOW PRES TO DVLP TO THE S AND MOVE NE INTO THE WTRS AND WILL RPDLY
INTSFY INTO HURN FORCE.

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

SUMMARY...12Z NCEP SFC ANALYSIS SHOWS A DEEP LOW CNTRD JUST E OF
NEWFOUNDLAND...WITH A COLD FNT EXTNDG SW FROM THE LOW PASSING E OF
BERMUDA...THEN SW INTO THE SRN BAHAMAS. A HI PRES RIDGE IS
BUILDING E OVER THE OFSHR WTRS. LATEST AVAIL ASCAT HI-RES PASSES
FROM THIS MRNG SHOW 25 TO 30 KT WINDS IN N TO NE FLOW OFF THE
NC/SC/GA COAST. LIGHTNING DENSITY PRODUCT DATA AT 1850Z DID NOT
SHOW ANY SHOWERS OR TSTMS OVER THE OFSHR WTRS. A WEAK COLD FNT
WILL PASS SE OVER THE NT1 AREA SUN AND SUN NITE. A VERY STRONG LOW
WILL PASS NE ACROSS THE NT2 WTRS SUN INTO MON...THEN MOVE OFF TO
THE NE LATE MON AND MON NITE. A DVLPG LOW WILL MOVE OFF THE MID
ATLC COAST MON NITE...MOVE NE ACROSS THE NRN NT2 WTRS TUE...THEN
MOVE OFF TO THE NE TUE NITE. A SERIES OF LOW PRES TROFS WILL MOVE
SE ACROSS THE NT1 AND NRN NT2 WTRS WED INTO THU NITE.

MODELS...THE 12Z MED RNG MDLS ARE SHOWING SOME MINOR TIMING AND
PATTERN DIFFS OVER THE NT1 AND NRN NT2 WTRS FOR TUE THRU THU...BUT
OVERALL THE 12Z GFS LOOKS REPRESENTATIVE ENUF TO BE USED FOR THE
WIND GRIDS THRU THE FCST PRD. THE 12Z GFS 10M LOOKS LIKE A GUD
MEDIAN MDL SOLN REGARDING THE STRENGTH OF THE LOW LOW FOR SUN
INTO MON...AND IT SUPPORTS MARGINAL HURCN FORCE WINDS WHICH LOOKS
REASONABLE FOR LATER SUN AND SUN NITE WITH VERY STRONG N TO NE
FLOW CROSSING THE GULF STREAM.

SEAS...BOTH THE 12Z WAVEWATCH III MDL AND 12Z ECMWF WAM
INITIALIZED REASONABLY WELL ACROSS THE OFSHR WTRS...ALTHO THE 12Z
WAVEWATCH III LOOKS UNDERDONE BY ABOUT 2 FT AROUND THE FAR ERN
PART OF THE GEORGES BANK WTRS. THE MDLS ARE IN DECENT AGREEMNT
OVERALL ACROSS THE OFSHR WTRS DURING THE FCST PRD...BUT AM
PLANNING TO GO WITH THE 12Z WNA WAVEWATCH III MDL FOR THE SEA HT
GRIDS...IN ORDER TO BE CONSISTENT WITH THE 12Z GFS WHICH IS THE
PREFERRED MDL FOR THE WIND GRIDS.

.EXTRATROPICAL STORM SURGE GUIDANCE...12Z ESTOFS IS SHOWING A
NEGATIVE SURGE IN THE 2 TO 2.5 FT RANGE NEAR THE SE COAST FOR SAT
NITE INTO SUN NITE...THEN A POSITIVE SURGE OF 1.5 TO 2 FT NEAR THE
MID ATLC AND NEW ENGLAND COASTS FOR SUN INTO EARLY MON. ALTHO
ESTOFS DOES LOOK REASONABLE IT IS VERY POSSIBLE IT COULD END UP
BEING UNDERDONE NEAR THE SE COAST.



.WARNINGS...PRELIMINARY.

.NT1 NEW ENGLAND WATERS...
.ANZ800...GULF OF MAINE...
     GALE SUN NIGHT INTO MON.
     GALE POSSIBLE MON NIGHT.
     GALE POSSIBLE THU INTO THU NIGHT.
.ANZ805...GEORGES BANK WEST OF 68W...
     GALE SUN NIGHT.
     STORM MON.
     GALE POSSIBLE WED INTO THU NIGHT.
.ANZ900...GEORGES BANK EAST OF 68W...
     GALE SUN NIGHT.
     STORM MON.
     GALE POSSIBLE WED INTO THU NIGHT.
.ANZ810...SOUTH OF NEW ENGLAND...
     GALE SUN NIGHT.
     STORM MON.
     GALE POSSIBLE WED INTO THU NIGHT.
.ANZ815...SOUTH OF LONG ISLAND...
     GALE SUN NIGHT INTO MON.
     GALE POSSIBLE TUE NIGHT INTO WED.
     GALE POSSIBLE THU INTO THU NIGHT.

.NT2 MID ATLC WATERS...
.ANZ820...HUDSON CANYON TO BALTIMORE CANYON...
     GALE SUN NIGHT.
     GALE POSSIBLE TUE NIGHT.
     GALE POSSIBLE WED NIGHT INTO THU NIGHT.
.ANZ915...HUDSON CANYON TO THE GREAT SOUTH CHANNEL...
     STORM SUN NIGHT INTO MON.
     GALE POSSIBLE TUE NIGHT INTO THU NIGHT.
.ANZ920...BALTIMORE CANYON TO THE GREAT SOUTH CHANNEL...
     GALE SUN.
     STORM SUN NIGHT INTO MON.
     GALE POSSIBLE MON NIGHT INTO THU NIGHT.
.ANZ905...THE GREAT SOUTH CHANNEL TO THE HAGUE LINE...
     STORM SUN NIGHT INTO MON.
     GALE POSSIBLE TUE.
     GALE POSSIBLE WED INTO THU NIGHT.
.ANZ910...EAST OF THE GREAT SOUTH CHANNEL AND SOUTH OF 39N...
     GALE SUN.
     STORM SUN NIGHT INTO MON.
     GALE POSSIBLE MON NIGHT INTO THU NIGHT.
.ANZ825...INNER WATERS FROM BALTIMORE CANYON TO CAPE CHARLES LIGHT...
     GALE SUN INTO SUN NIGHT.
     GALE POSSIBLE THU.
.ANZ828...INNER WATERS FROM CAPE CHARLES LIGHT TO CURRITUCK BEACH LIGHT...
     GALE SUN.
     STORM SUN NIGHT.
.ANZ925...OUTER WATERS FROM BALTIMORE CANYON TO HATTERAS CANYON...
     GALE SUN.
     STORM SUN NIGHT INTO MON.
     GALE POSSIBLE MON NIGHT INTO THU.
.ANZ830...INNER WATERS FROM CURRITUCK BEACH LIGHT TO CAPE HATTERAS...
     STORM SUN INTO SUN NIGHT.
     GALE POSSIBLE MON NIGHT INTO TUE.
     GALE POSSIBLE WED NIGHT.
.ANZ833...INNER WATERS FROM CAPE HATTERAS TO CAPE FEAR...
     GALE TONIGHT.
     STORM SUN INTO SUN NIGHT.
     GALE POSSIBLE MON NIGHT INTO WED NIGHT.
.ANZ930...OUTER WATERS FROM HATTERAS CANYON TO CAPE FEAR...
     STORM SUN INTO MON.
     GALE POSSIBLE MON NIGHT INTO WED NIGHT.
.ANZ835...INNER WATERS FROM CAPE FEAR TO 31N...
     GALE TONIGHT.
     STORM SUN.
     HURRICANE FORCE SUN NIGHT.
     GALE POSSIBLE MON NIGHT INTO WED NIGHT.
.ANZ935...OUTER WATERS FROM CAPE FEAR TO 31N...
     STORM SUN.
     HURRICANE FORCE SUN NIGHT.
     GALE MON.
     GALE POSSIBLE MON NIGHT INTO WED NIGHT.

$$

.FORECASTER MUSONDA/SCOVIL. OCEAN PREDICTION CENTER.



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