000
AGXX40 KNHC 121800
MIMATS

MARINE WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
200 PM EDT MON AUG 12 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/OFFICIAL/NWW3 BLEND WITH HIGH CONFIDENCE
THROUGH WED...LOW CONFIDENCE THEREAFTER.  

RIDGE EXTENDS FROM 1020 MB HIGH PRES CENTER OFF NE FLORIDA COAST
ALONG 29N INTO NW GULF.  GUIDANCE AGREE ON LITTLE CHANGE THROUGH
WED.  RIDGE WEAKENS AS MAIN HIGH PRES CENTER SHIFT E ALLOWING
DEVELOPING LOW PRES OVER NW CARIBBEAN TO DRIFT NW INTO EASTERN
GULF LATE WED.  MODELS DIFFER THEREAFTER AS POSITION...TRACK...
TIMING AND STRENGTH OF LOW PRES WITH MOST AGGRESSIVE GFS 
BRINGING 1006 MB LOW PRES CENTER INTO FLORIDA PANHANDLE OR MORE
MODERATE UKMET AND ECMWF BRINGING A MUCH WEAKER LOW PRES FURTHER
W OF 87W.  OTHER MODEL SOLUTIONS BRING EVEN WEAKER LOW PRES EVEN
FURTHER W. UNCERTAINTY ON THE DETAILS DOES NOT PRECLUDE THE MAIN
FACT THAT THE NORTHEASTERN GULF WILL BE WET AND POSSIBLY WINDY
LATE IN THE FORECAST PERIOD.

...CARIBBEAN SEA AND TROPICAL N ATLANTIC...                    
MODEL PREFERENCE: GFS/OFFICIAL BLEND WITH MEDIUM CONFIDENCE DUE
TO TIMING OF DEVELOPING LOW PRES. 

DUAL CENTERED UPPER LEVEL CYCLONIC CIRCULATION HAS ONE FOCUS
OVER WESTERN HALF OF CUBA AND A SECOND OVER HISPANIOLA.  SURFACE
TROUGH DRAGS W ALONG 70W WHILE DEVELOPING 1009 MB LOW PRES WAITS
AT 11N81W TO BRING ITS ABUNDANT WARM TROPICAL MOISTURE INTO THE
SCENE.  PRES GRADIENT ALREADY TIGHTENING AS SHOWN BY OBSERVED
FRESH TO STRONG EASTERLY BREEZE IN CENTRAL CARIBBEAN ALONG WITH
SEAS 8-9 FT.  

GUIDANCE SOLUTIONS POINT TO DEVELOPMENT OF LOW PRES IN SOUTHWEST
CARIBBEAN AND SLOW STRENGTHENING THROUGH TUE AS IT DRIFT NW INTO
GULF OF HONDURAS AND EVENTUALLY INTO GULF OF MEXICO BY LATE WED.
NUMEROUS MODERATE TO STRONG CONVECTION MAY PRODUCE UNSAFE MARINE
CONDITIONS MAINLY E OF LOW PRES. 
 
TROPICAL WAVE CURRENTLY ALONG 56W APPROACHES LESSER ANTILLES
LATER TODAY...BUT IS EXPECTED TO LOSE DEFINITION AS IT DRIFTS
INTO ATLC RIDGE SHIFTING SE.  RIDGE ALLOW FRESH TO STRONG TRADES
TO PERSIST MAINLY ACROSS THE CENTRAL CARIBBEAN THROUGH REMAINDER
OF PERIOD.  LITTLE WEATHER EXPECTED ALONG TROPICAL WAVE AS IT
FACES A DRY AIR MASS AHEAD OF IT. 

...SW N ATLANTIC W OF 55W INCLUDING THE BAHAMAS...           
MODEL PREFERENCE: GFS/ECMWF/OFFICIAL BLEND WITH HIGH CONFIDENCE.
MWW3 FOR WAVE HEIGHTS.

HIGH PRES CENTER 1020 MB AT 29N75W HAS RIDGE EXTEND ALONG 29N
THROUGH BASIN. LIGHT NE-E BREEZE WITH 2-4 FT SEAS ACROSS REGION
N OF 25N AND GENTLE TO MODERATE BREEZE NOTED S OF 25N. MODELS
AGREE RIDGE DRIFTING E-SE WITH LIGHT SOUTHERLY BREEZE W OF 75W.
LITTLE CHANGE EXPECTED IN WINDS OR SEA CONDITIONS THROUGH PERIOD.

$$

.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.