Marine Interpretation Message
Issued by NWS

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
000
AGNT40 KWNM 231159
MIMATN

MARINE WEATHER DISCUSSION FOR N ATLANTIC OCEAN
NWS OCEAN PREDICTION CENTER WASHINGTON DC
759 AM EDT SAT AUG 23 2014

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

SLOWED DOWN TIMING OF PSBL TRPCL CYCLONE BY ABOUT 12 HOURS FROM
PREV FCST. THIS IS MORE IN LINE WITH LATEST MODEL TRENDS. HIGH
UNCERTAINTY STILL REMAINS CONCERNING THIS SYSTEM...WITH LOW FCST
CONFDC. HOWEVER...LATEST UKMET AND CANADIAN WHICH HAD SYSTEM
MOVING INTO THE GULF...NOW SHOWS A BIT OF A RECURVATURE. ONLY
OTHER MAJOR DIFFERENCE NOTED IS THAT MODEL CONSENSUS...OR THE
ATTEMPT AT MODEL CONSENSUS...HAS SHIFTED FURTHER W THAN
YESTERDAY...WHICH SEEMS TO INCR THE THREAT OF SYSTEM DIRECTLY
AFFECTING THE OFFSHR WATERS.

OTW...NO SIG CHANGES IN THE FCST.

SEAS...WNA VERSION OF WWIII WITHIN A FT OR TWO OF CURRENT OBS. DID
SLOW BUILDING OF SEAS BY ABOUT 12 HOURS...TO MATCH UP WITH THE
TIMING OF THE WIND FIELD. OTW...NO SIG CHANGES.


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

QUIET SUMMERTIME WEATHER WILL CONTINUE OVER THE WRN ATLC THROUGH
MON...THEN A PSBL TRPCL CYCLONE WILL LIKLEY AFFECT PARTS OF THE
REGION FM LATE TUE ON. COLD FRONT W TO E ACROSS THE WATERS S OF
HTTRS CANYON WILL SLOWLY PUSH S OVR THE SRN WATERS TODAY AND TNGT
AS HIGH PRES BUILDS SE INTO THE RGN. THE GFS/UKMET/ECMWF INCRS NE
WIND TO 25 KT S OF HTTRS CNYN SUN AS THE HIGH PRESSES S. WILL USE
THE SLGTLY HIGHER GFS 30M WINDS AS THE MODELS TEND TO UNDER
ESTIMATE WINDS IN THE NE FLOW.

TONIGHTS MODEL RUNS SHOW BETTER AGREEMENT WITH THE PSBL TROPICAL
CYCLONE FCST TO MOVE N INTO THE SRN WATERS TUE NIGHT INTO EARLY
WED. HOWEVER...THERE IS STILL QUITE A BIT OF UNCERTAINTY...THOUGH
GALE/TRPCL STORM FRC WINDS FOR THE SRN WATERS FOR WED AND WED
NIGHT SEEM FAVORABLE. WILL LEAN TWDS THE LATEST ECMWF WHICH STAYS
CLOSEST TO PRVS FCST GRIDS...AND WILL SLOW IT BY 6 HOURS. THE
CYCLONE MVNG INTO THESE WATERS HAS A HIGH PROB OF BCMG TRPCL
WITHIN THE NEXT 48 HRS...AND A TRPCL STORM FORCE WINDS...OR
HIGHER OVER THESE WATERS BY MID WEEK SEEM QUITE PLAUSEABLE.

.SEAS...THE WAVEWATCH MODEL IS WITHIN A FT OR LATEST OBSVRTNS.
WILL STAY CLOSE TO THE WAVEWATCH THRU TUE...THEN USE A 50/50 BLEND
OF THE ECMWF WAM WHICH HAS HIGHER SEAS OVR THE SRN WATERS. IF A
TRPCL CYCLONE MVS INTO THE WATERS...THESE SEAS WL BE TOO LOW BUT
AT LEAST THEY ARE LIEKLY MORE REALISTIC THEN THE LOWER WAVEWATCH
MODEL SEAS.


.EXTRATROPICAL STORM SURGE GUIDANCE...



.WARNINGS...PRELIMINARY.

.NT1 NEW ENGLAND WATERS...
     NONE.

.NT2 MID ATLC WATERS...
     NONE.

$$

.FORECASTER ACHORN/PROSISE. OCEAN PREDICTION CENTER.



USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.