000
AGXX40 KNHC 200813
MIMATS

MARINE WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
413 AM EDT FRI SEP 20 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: OFFICIAL FORECAST BLENDED WITH LATEST GFS.
LOW TO MEDIUM CONFIDENCE DUE TO DIFFERENCES IN HANDLING LOW PRES
OUT OF BAY OF CAMPECHE.

LOW PRES CENTER AT 21N96W 1004 MB DRIFT W-NW AT 5 KT THROUGH EARLY
SAT REACHING 25N95W THEN CONTINUE INLAND MEXICO. FRESH TO STRONG
WINDS WITHIN 75 NM OF LOW PRES CENTER AND ALSO FROM 21N TO 24N
W OF 88W. SEAS BUILD TO 7-8 FT N OF 22N W OF 92W...4-6 FT
ELSEWHERE W OF 90W AND 1-3 FT E OF 90W.

MODEL GUIDANCE IN DISAGREEMENT ON LOW PRES TRACK...REASON FOR LOW
CONFIDENCE...WITH OFFICIAL TURNING IT W AFTER SAT WHILE SOME
MODELS PUSHING IT FURTHER N INTO TAIL END OF COLD FRONT. IF SO...
FRONT WOULD MERGE INTO COLD FRONT OR DISSIPATE NEAR COAST OF
MEXICO SUN. FRONT EXPECTED TO STALL ACROSS NORTHERN GULF
WATERS...WEAKENING THROUGH TUE. UNCERTAINTY RULES.

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

MODEL PREFERENCE: OFFICIAL FORECAST BLENDED WITH LATEST GFS. NWPS
USED FOR WAVE PARAMETERS. HIGH CONFIDENCE.

LOW PRES AND ATTENDANT TROUGH OVER SE N ATLC HAS FLATTEN PRES
GRADIENT BRINGING GENTLE TO MODERATE E-SE BREEZE ACROSS BASIN E OF
80W. A FRESH SE BREEZE WITH SEAS 5-6 FT STILL LINGERS W OF 80W DUE
TO SECOND LOW PRES OVER BAY OF CAMPECHE. AS SW N ATLC LOW PRES
CENTER MOVES NE...HIGH PRES BUILDS AND TIGHTENS GRADIENT AGAIN
INCREASING E WINDS ACROSS ENTIRE CARIBBEAN TO A FRESH BREEZE. 
SEAS BUILD TO 6-8 FT. 

TROPICAL N ATLC...CURRENT STEADY FLOW OF GENTLE TO MODERATE E-SE
BREEZE AND 4-5 FT SEAS LIKELY REMAIN WITH MINOR INCREASES AS
RIDGE REBUILDS N OF AREA.

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

MODEL PREFERENCE: OFFICIAL FORECAST BLENDED WITH GFS.
MEDIUM TO HIGH CONFIDENCE DUE TO TIMING OF LOW PRES TRACK.

WEAK STATIONARY FRONT ALONG 29N E OF 70W MAY BE TRIGGER TO PICK UP
LOW PRES 1011 MB THAT FORMED AT 26N70W. TIGHT GRADIENT WITH
REBUILDING RIDGE LIKELY TO PRODUCE FRESH TO STRONG WINDS OVER
NORTHWEST QUADRANT WITH 6-7 FT SEAS. GENTLE TO MODERATE ELSEWHERE
WITH SEAS 3-4 FT. EXCEPT 1-3 FT SEAS W OF BAHAMAS.

COLD FRONT FORECAST TO ENTER NW CORNER OF BASIN LATE SUN OR MON.

$$

.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 WALLY BARNES. NATIONAL HURRICANE CENTER.