Marine Interpretation Message
Issued by NWS

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AGNT40 KWNM 070701
MIMATN

MARINE WEATHER DISCUSSION FOR N ATLANTIC OCEAN
NWS OCEAN PREDICTION CENTER WASHINGTON DC
301 AM EDT THU MAY 7 2015

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

OVER THE SHORT TERM...THE MOST SIG WX FEATURE TO AFCT THE
CSTL/OFSHR WTRS WL BE THE POTENTIAL DVLPG TROPICAL AND/OR
SUBTROPICAL LOW NOW JUST S OF THE NT2 WTRS. IN RGRDS TO THE FCST
TRACK OF THIS SYSTEM...THE DIFFERENCES BTWN THE 00Z MDLS HV
NARROWED SIGLY THRU FRI NITE (WITH THE 00Z ECMWF/GEM TRACKS A
SHADE TOO THE E) WITH THE LOW DRIFTING SLOWLY N THEN NW TO OFF THE
S CAROLINA COAST BY SAT MORNING. AS A RESULT OVERALL BLV THE 00Z
GFS TRACK...WHICH IS ALSO SPRTD BY THE 00Z GEFS MEAN...NOW LOOKS
REPRESENTATIVE THRU THE SHORT TERM. IN RGRDS TO THE SHORT TERM
FCST GRADIENTS ASCD WITH THIS SYSTEM...BLV THE 00Z GFS SOLUTION
LOOKS REPRESENTATIVE AND AS A RESULT PLAN ON POPULATING OUR SHORT
TERM FCST WIND GRIDS WITH ITS 30M BL WINDS...WITH SM ADDITIONAL
FURTHER EDITS IN DEFERENCE MAINLY TO THE VERY SMLR 00Z UKMET BL
WINDS. SO SINCE THE 12Z UKMET BL WINDS WERE USED FOR THE PREV
OFSHR FCST PACKAGE DO NOT ANTICIPATE MAKING ANY MAJOR SHORT TERM
CHNGS IN THE NEXT FCST PACKAGE THRU FRI NITE.

IN THE LONG RANGE...THE 00Z NAM/GFS/GEM/ECMWF ARE IN RSNBLY GOOD
AGRMT THAT THE LOW WL DRIFT EVER SO SLOWLY N SAT AND THEN BE OFF
THE S AND N CAROLINA BORDER BY SUN MORNING WHICH LOOKS RSNBL BUT
BCMS SLOWER THAN THE NOW MR PROGRESSIVE 00Z UKMET. THEN THE 00Z
GLOBAL MDLS START TO DIVERGE IN HOW FAST THE LOW WL GET CAUGHT UP
BY THE UPR LVL FLOW AND START TO GRADLY ACCELERATE TO THE NE SUN
NITE INTO MON NITE. FOR NOW AS A COMPROMISE...WULD FAVOR A BLENDED
00Z GFS/ECMWF FCST TRACK FOR THIS NE ACCELERATION...WHICH IS
SLIGHTLY SLOWER THAN THE 00Z UKMET AND MR IN LINE WITH THE PREVLY
NHC COORDINATED WPC MEDIUM RANGE GUIDANCE. THEREFORE WL CONT TO
POPULATE WITH THE 00Z GFS 30M BL WINDS ON SAT INTO SUN NITE...THEN
WL TRANSITION TO POPULATING WITH THE MR CONSERVATIVE 00Z GFS 10M
BL WINDS (TO AGAIN COMPROMISE WITH THE WEAKER 00Z ECMWF SOLUTION)
ON MON/MON NITE TIME SHIFTED 3 HRS FASTER TO ASSIMILATE A
COMPROMISE 00Z GFS/ECMWF TRACK. SO AS A RESULT WL BE MAKING SM SIG
LONG RANGE CHNGS IN THE NEXT OFSHR FCST PACKAGE.

.SEAS...SINCE THE 00Z GFS WL BE FAVORED...WL POPULATE OUR FCST
WAVE GRIDS WITH THE 00Z WAVEWATCH III FOR TODAY THRU SUN NITE.
THEN SINCE A COMPROMISE 00Z GFS/ECMWF SOLUTION WL BE USED...WL
TRANSITION TO A 50/50 BLEND OF THE 00Z ECMWF WAM AND THE 00Z
WAVEWATCH III (TIME SHIFTED CORRESPONDINGLY 3HRS FASTER) ON
MON/MON NITE.

.EXTRATROPICAL STORM SURGE GUIDANCE...AS THE LOW MEANDERS OFF
THE SE COAST INTO SUN THE 00Z ESTOFS FCSTS A SLIGHTLY HIGHER
POSITIVE SURGE (BY ABOUT .5 FT ON AVERAGE) THAN FCST BY THE 00Z
ETSS ALONG THE SE COAST S OF CP HAT...WHICH IF ANYTHING MAY BE
SLIGHTLY UNDERDONE BUT FOR NOW LOOKS RSNBL.

.WARNINGS...PRELIMINARY.

.NT1 NEW ENGLAND WATERS...
     NONE.

.NT2 MID ATLC WATERS...
.ANZ915...HUDSON CANYON TO THE GREAT SOUTH CHANNEL...
     GALE POSSIBLE MON NIGHT.
.ANZ920...BALTIMORE CANYON TO THE GREAT SOUTH CHANNEL...
     GALE POSSIBLE MON NIGHT.
.ANZ925...OUTER WATERS FROM BALTIMORE CANYON TO HATTERAS CANYON...
     GALE POSSIBLE MON NIGHT.
.ANZ833...INNER WATERS FROM CAPE HATTERAS TO CAPE FEAR...
     GALE TODAY INTO FRI.
     GALE POSSIBLE SAT.
     GALE POSSIBLE SUN INTO SUN NIGHT.
.ANZ835...INNER WATERS FROM CAPE FEAR TO 31N...
     GALE EARLY TODAY INTO FRI NIGHT.
     GALE POSSIBLE SAT INTO SUN NIGHT.
.ANZ935...OUTER WATERS FROM CAPE FEAR TO 31N...
     GALE TODAY INTO FRI NIGHT.
     GALE POSSIBLE SAT.

$$

.FORECASTER VUKITS. OCEAN PREDICTION CENTER.


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