000
AGXX40 KNHC 110800
MIMATS

MARINE WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
400 AM EDT SUN AUG 11 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/ECMWF/OFFICIAL BLEND WITH HIGH CONFIDENCE.
NWPS FOR WAVE HEIGHTS.

A WEAK 1013 MB SURFACE LOW IS CENTERED OVER THE SW GULF NEAR
22N94W...ALONG A TROUGH FROM 25N96W TO 19N93W. THE NORTHERN
PORTION OF A WEAKENING TROPICAL WAVE MOVING INTO THE SW GULF HAS
COME INTO PHASE WITH THE TROUGH AND IS NOW INDISTINGUISHABLE FROM
IT. THE MERGED TROUGH IS SUPPORTED BY AN UPPER LOW CENTERED OVER
THE SW GULF NEAR 22N94W...SLOWLY MOVING W ACROSS THE REMAINDER OF
THE GULF AND WILL SHIFT INTO CENTRAL MEXICO BY EARLY MON WITH THE
SURFACE TROUGH GRADUALLY BECOMING DIFFUSE ALONG THE COAST OF
VERACRUZ THROUGH TUE. ELSEWHERE THERE IS GOOD MODEL CONSENSUS AND
CONTINUITY SHOWING A RIDGE WILL BUILD FROM THE WESTERN ATLC ACROSS
THE NORTHERN GULF. THIS WILL MAINTAIN LIGHT WINDS ACROSS THE NE
AND N CENTRAL GULF THROUGH MID WEEK. LIGHT TO MODERATE WINDS WILL
PERSIST OVER THE SOUTHERN GULF...WITH OCCASIONALLY WINDS TO 20 KT
ACROSS THE STRAITS OF FLORIDA. SEAS WILL BE 2 TO 4 FT OVERALL.

...CARIBBEAN SEA AND TROPICAL N ATLANTIC...                    
MODEL PREFERENCE: GFS WITH HIGH CONFIDENCE. NWPS FOR WAVE HEIGHTS.

LATEST BUOY OBSERVATIONS AND SCATTEROMETER DATA INDICATE A LARGE
SWATH OF 20 KT ACROSS WINDS OVER MUCH OF THE CENTRAL CARIBBEAN
THIS MORNING...WITH UP TO 25 KT WITHIN 90 NM OF THE COAST OF
HISPANIOLA. THE ENHANCED FLOW IS DUE TO 1021 MB HIGH PRES
CENTERED N OF THE AREA BETWEEN BERMUDA AND NE FLORIDA MAINTAINING
A FAIRLY TIGHT GRADIENT ACROSS THE BASIN. BUOY 42059 NEAR 15N67W
IS SHOWING SEAS TO 8 FT...WITH EARLIER ALTIMETER PASSES SHOWING 5
TO 7 FT OVER THE CENTRAL CARIBBEAN. ELSEWHERE MODERATE TRADES
PREVAIL. THE WINDS WILL DIMINISH SLIGHTLY OVER THE NEXT 24 TO 48
HOURS AS A TROUGH NOW FORMING OVER THE FAR EASTERN CARIBBEAN
MIGRATES W THROUGH MID WEEK. THE TROUGH IS NOT ACTUALLY A TROPICAL
WAVE AKA AFRICAN EASTERLY WAVE...BUT INSTEAD IS A PRODUCT OF AN
UPPER LOW CENTERED OVER THE NE CARIBBEAN NEAR 17N65W. THIS HAS
BEEN THE DOMINANT PATTERN LATELY WITH UPPER LOWS PASSING E TO W
ACROSS THE NORTHERN CARIBBEAN. A MORE CLASSIC TROPICAL WAVE IS
APPROACHING THE AREA FARTHER TO THE EAST...AND WILL WEAKEN
CONSIDERABLY AS IT MOVES INTO THE EASTERN CARIBBEAN LATE MON.
MEANWHILE THE UPPER LOW AND ITS ASSOCIATED SURFACE TROUGH WILL
SWEEP WESTWARD...WITH THE TROUGH AMPLIFYING OVER THE CENTRAL AND
WESTERN CARIBBEAN THROUGH MID WEEK. THE NET IMPACT WILL BE A
SLIGHT DIMINISHMENT IN THE WINDS IN THE SHORT TERM...WITH AN
INCREASE IN TRADES STARTING MID WEEK AS HIGH PRES N OF THE AREA
BUILDS ACROSS THE BASIN.

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

1021 MB SURFACE HIGH IS CENTERED BETWEEN BERMUDA AND NE FLORIDA
NEAR 20N73W. THIS IS MAINTAINING RELATIVELY LIGHT WINDS N OF
25N...WITH MODERATE TRADES FARTHER S AND UP TO 20 KT S OF 22N. THE
RIDGE WILL SHIFT S BY MID WEEK...WITH LITTLE CHANGE IN CONDITIONS
EXPECTED. 

$$

.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 CHRISTENSEN. NATIONAL HURRICANE CENTER.