000
AGXX40 KNHC 230814
MIMATS

MARINE WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
414 AM 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: GFS BLEND WITH GOOD CONFIDENCE.

WELL DEFINED STATIONARY LOW PRES CENTER 1003 MB AT 26N94W MERGED
EARLIER TODAY WITH STALLED COLD FRONT AND FORCES TAIL END W OF 87W
TO THE N AS WARM FRONT. GFS HAS HAD GOOD HANDLE ON FEATURE THEN 
ELONGATES LOW PRES TO THE NE MON AND EVENTUALLY DRAGS IT INLAND
NEAR MOBILE ALABAMA. OTHER DYNAMIC MODELS FOLLOW SUIT WITH BOTH
LOW PRES AND FRONT WITH UNCANNY SIMILARITY...ADDING CERTAINTY TO
FORECAST. NUMEROUS MODERATE AND ISOLATED STRONG CONVECTION BECOMES
THE MAIN WEATHER FEATURE AS WINDS AND SEAS DIMINISH SIGNIFICANTLY
AROUND LOW PRES AND FRONT AS SOURCE OF ENERGY...AN UPPER LEVEL
SHORTWAVE...MOVED NE QUICKLY EARLIER TODAY. MODERATE TO FRESH
WINDS CIRCLE LOW PRES CENTER AND SEAS REMAIN 5-6 FT TODAY THEN
DIMINISH EVEN FURTHER AS CENTER ELONGATES AND DRIFTS NE. TROUGH
DRAGS SW FROM LOW PRES CENTER WITH LIGHT TO GENTLE NE FLOW WITH
SEAS 3-4 FT NW OF TROUGH AND MODERATE SW BREEZE WITH 4-5 FT SEAS
ON SE SIDE OF TROUGH BY LATE TUE. WEAK RIDGE BUILD IN BEHIND LOW
PRES WITH LIGHT TO GENTLE BREEZE AND SEAS 2-3 FT THROUGH FRI.

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

MODEL PREFERENCE: GFS WITH GOOD CONFIDENCE GIVEN PREVIOUS HANDLE
ON CONDITIONS.

FRESH TRADES CONTINUE TODAY ACROSS S CENTRAL PORTIONS OF BASIN WITH
SEAS 6-8 FT...WHILE MODERATE E-SE FLOW REMAINS ON EITHER SIDE AND
IN TROPICAL N ATLC ZONE. HIGH PRES RIDGE OVER CENTRAL ATLC KEEPS
TIGHT GRADIENT ACROSS AREA BUT RECEDES EARLY THU AS NEW ATLC COLD
FRONT PUSHES IT FURTHER E. WIND AND SEA THEN SUBSIDE TO A MODERATE
E BREEZE AND SEAS TO 4-6 FT THROUGH FRI. TROPICAL WAVE APPROACHING
TROPICAL N ATLC WATERS EARLY WED EXPECTED TO SHIFT MORE TO THE N
AND PASS ACROSS N PORTIONS WITH LITTLE EFFECT ON ZONE. 

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

MODEL PREFERENCE: GFS BLEND WITH CONSENSUS WITH MEDIUM TO LOW 
CONFIDENCE DUE TO LARGE DIFFERENCES IN MODEL SOLUTIONS.

COLD FRONT JUST N OF 31N BRIEFLY INCREASING SW-W WINDS AND SEAS N
OF 29N EXPECTED TO SUBSIDE BY EARLY TUE. LOW PRES CENTER AND
ASSOCIATED COLD FRONT ENTERS SW N ATLC LATE TUE NIGHT OR EARLY
WED AND RUSHES THROUGH BASIN BRINGING SUDDEN INCREASE TO NEAR GALE
FORCE SW WINDS AND SEAS TO 12 FT THROUGH FRI. WITH ABUNDANT MOISTURE
READILY AVAILABLE...STRONG CONVECTION IS LIKELY IN VICINITY OF 
FRONTAL BOUNDARY AND LOW PRES CENTER. GFS FASTER AND STRONGER THAN
OTHER MODELS...SO BLEND TAKES MIDDLE OF ROAD APPROACH TO LOW PRES
INTENSITY. 

$$

.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...GALE CONDITIONS EXPECTED THU INTO THU NIGHT. 
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 WALLY BARNES. NATIONAL HURRICANE CENTER.