000
AGXX40 KNHC 231854
MIMATS

MARINE WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
254 PM EDT MON SEP 23 2013

MARINE WEATHER DISCUSSION FOR THE GULF OF MEXICO...CARIBBEAN
SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND
64W...AND THE SW N ATLANTIC INCLUDING THE BAHAMAS.

...GULF OF MEXICO...

MODEL PREFERENCE: GEFS MEAN.

LOW PRES CONTINUES ACROSS NW GULF ANALYZED AT 1005 MB AT 18Z AND
IS LIKELY BEGINNING TO OCCLUDE. WARM FRONT EXTENDS ENE FROM LOW
ALONG GULF COASTAL WATERS AND INLAND ACROSS FL PANHANDLE. 20 KT
FLOW STILL BEING REPORTED BY SOME BUOYS AND RIGS ACROSS N AND NW
QUADS OF LOW...WITH SEAS BACK UP TO 7 FT AT 42019. LOW EXPECTED
TO GRADUALLY SPIN DOWN AND OPEN UP INTO WEAK LOW BY 48 HRS THEN TO
DISSIPATING TROUGH BY 72 HOURS AS IT SHIFTS SLOWLY E. SLY FLOW
THROUGH YUCATAN CHANNEL OVERNIGHT CONTINUES ATTM INTO SE GULF WITH
SEAS 5-6 FT ACROSS SE PORTIONS AND BUILDING 3-5 FT NE PART...WHILE
RECENT ASCAT PASS SHOWED S WINDS 15-20 KT ACROSS MUCH OF SE PART.
EARLIER ALTIMETER PASS ALONG W GULF COAST INDICATED SEAS 6-7 FT
STILL LINGERING 22-24N ACROSS MEXICAN COASTAL WATERS AND WILL BE
SLOWER COMING DOWN THAN INDICATED BY WW3 AS NNE FETCH IN NW QUAD
OF LOW HAS GENERATED 9S WIND SWELL STILL PROPAGATING SWD. FRONT TO
LIFT WELL INLAND TONIGHT THROUGH WED AS NEXT S/W SWEEPS ACROSS
CENTRAL U.S. AND OFF E COAST THU. THERE ARE STILL SIGNIFICANT
TIMING DIFFERENCES IN GLOBAL MODELS THAT ARE MINOR IN THE SHORT
TERM ACROSS THE GULF...BUT VERY SIGNIFICANT ACROSS ATLC.

...CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN
55W AND 65W...

MODEL PREFERENCE: GFS 

FRESH TRADES CONTINUE TODAY ACROSS CENTRAL PORTIONS OF BASIN WITH
SEAS 6-9 FT...WHILE MODERATE E TO SE FLOW REMAINS ON EITHER SIDE
AND MILD ELY TRADES IN TROPICAL N ATLC ZONE. RECENT ASCAT PASS
SHOWING BROADENING AREA OF 20-25 KT TRADES EXTENDING ALL THE WAY
TO SW COAST OF HAITI. HIGH PRES RIDGE OVER E CENTRAL ATLC HAS
BEGUN TO BUILD WEAKLY W ALONG 24.5N AND WILL KEEP SUFFICIENT PRES
GRADIENT ACROSS AREA FOR FRESH TRADES CENTRAL PORTIONS THROUGH
WED...THEN RECEDE EARLY THU AS NEW ATLC COLD FRONT PUSHES IT
FURTHER E. WEAK TROPICAL WAVE APPROACHING TROPICAL N ATLC WATERS
TO MOVE NW ACROSS N PORTIONS EARLY WED AND GRADUALLY DISSIPATE
THROUGH THU.

...SW N ATLANTIC INCLUDING THE BAHAMAS...

MODEL PREFERENCE: GEFS MEAN THROUGH DAY 2 THEN BLEND UKMET.

COLD FRONT HAS SUNKEN INTO NW WATERS AS FORECAST WITH RECENT ASCAT
PASS SHOWING SW WINDS 20-25 KT BETWEEN 70-74W N OF 29N THAT I HAD
DISCOUNTED FOR HSF...BUT WILL HAVE TO ADD BACK IN FOR 18Z
ISSUANCE. ANTICYCLONIC FLOW TO S AND SE OF THIS FEATURE WILL
REMAIN ESTABLISHED NEXT FEW DAYS AS E CENTRAL ATLC RIDGE BUILDS
WWD ALONG 24N AND S/W ENERGY SWEEPS SERIES OF LLVL VORT MAXES
ACROSS N PORTIONS AND ALONG FRONTAL BOUNDARY. NW PORTION OF FRONT
FCST TO REMAIN ANCHORED ACROSS N FL AND BE PUSHED SE ACROSS N
WATERS E OF 75W. AS MENTIONED PAST DAYS AND ABOVE...SIGNIFICANT
TIMING DIFFERENCES OCCUR WITH LOWS COMING OUT OF SE U.S. AND MOVED
ENE ALONG FRONT...WITH GFS FASTEST AND DEVELOPING SMALLER
LOW...WHILE ECMWF AND UKMET SLOWER AND DEVELOP LARGE BAROCLINIC
LOW ACROSS W ATLC. GEFS MEAN IS CLOSEST TO UKMET SO HAVE CHOSEN TO
NUDGE FORECAST IN THAT DIRECTION WITH 1007 MB LOW ALONG 30N78W AT
48 HRS AND 1004 MB LOW AT 30N71.5W AT 72 HRS...THEN SHIFTING NE
AND DEEPENING. NE OR NNE FLOW FILLING IN ACROSS W ATLC BEHIND LOW
WILL SPRAY SWELL AT FLORIDA AND FAR NW WATERS THU AND
FRI...POTENTIALLY MORE NLY IF ECMWF VERIFIES. 20-30 KT OF SW FLOW
EXPECTED SW SEMICIRCLE OF LOW BY 72 HOURS WITH SEAS BUILDING 6-9
FT.

$$

.WARNINGS...ANY CHANGES IMPACTING COASTAL NWS OFFICES WILL BE
COORDINATED THROUGH AWIPS 12 PLANET CHAT OR BY TELEPHONE:

.GULF OF MEXICO...
GMZ011...NONE.
GMZ013...NONE.
GMZ015...NONE.
GMZ017...NONE.
GMZ019...NONE.
GMZ021...NONE.
GMZ023...NONE.
GMZ025...NONE.

.CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN
55W AND 64W...
AMZ011...NONE.
AMZ013...NONE.
AMZ015...NONE.
AMZ017...NONE.
AMZ019...NONE.
AMZ021...NONE.
AMZ023...NONE.
AMZ025...NONE.
AMZ027...NONE.
AMZ029...NONE.
AMZ031...NONE.
AMZ033...NONE.
AMZ035...NONE.
AMZ037...NONE.
AMZ039...NONE.

.SW N ATLANTIC INCLUDING THE BAHAMAS...
AMZ111...NONE.
AMZ113...NONE.
AMZ115...NONE.
AMZ117...NONE.
AMZ119...NONE.
AMZ121...NONE.
AMZ123...NONE.
AMZ125...NONE.
AMZ127...NONE.

*FOR DETAILED ZONE DESCRIPTIONS PLEASE VISIT:
HTTP://WWW.NHC.NOAA.GOV/ABOUTTAFBPROD.SHTML#OWF

NOTE: GRIDDED MARINE FORECASTS ARE AVAILABLE IN THE
NATIONAL DIGITAL FORECAST DATABASE (NDFD) AT:
HTTP://WWW.NHC.NOAA.GOV/MARINE/GRIDS.PHP

FOR ADDITIONAL INFORMATION PLEASE VISIT:
HTTP://WWW.HURRICANES.GOV/MARINE

$$
.FORECASTER STRIPLING. NATIONAL HURRICANE CENTER.