000
AGXX40 KNHC 270705
MIMATS

MARINE WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
305 AM EDT THU JUN 27 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: BLEND OF PREVIOUS OFFICIAL FORECAST WITH 
GFS/ECMWF FOR MARINE WINDS AND WW3/NWPS FOR SEA HEIGHTS. HIGH 
CONFIDENCE BASED ON PERSISTENCE AND GOOD AGREEMENT IN MODELS.

WEAK RIDGE CONTINUES ACROSS BASIN ALONG 29N WITH RECENT SCAT 
PASSES SHOWING GENTLE WINDS 10 KT OR LESS OVER MOST OF THE 
REGION EXCEPT STRAITS OF FLORIDA. HIGHEST SEAS ARE NEAR 4 FT 
ALONG TEXAS COAST AND MAINLY 1-2 FT ELSEWHERE. THE RIDGE WILL 
SHIFT SLOWLY SOUTHWARD LATER IN THE WEEK AS A WEAK HIGH DEVELOPS 
WITHIN RIDGE ACROSS THE CENTRAL GULF FRI. TAIL END OF WEAK COLD 
FRONT WILL REACH THE NORTHERN GULF COAST SAT...WITH WINDS 
INCREASING AND SHIFTING W-SW NORTH OF A RIDGE AXIS DISPLACED 
FURTHER SOUTH ALONG 24N.

...CARIBBEAN SEA AND TROPICAL N ATLANTIC...                    
MODEL PREFERENCE: BLEND OF PREVIOUS OFFICIAL FORECAST WITH 
GFS/ECMWF FOR MARINE WINDS AND WW3/NWPS FOR SEA HEIGHTS. HIGH 
CONFIDENCE BASED ON PERSISTENCE AND GOOD AGREEMENT IN MODELS.

WEAK BUT PERSISTENT W ATLC RIDGE ALONG 29N YIELDING WEAK PRES 
GRADIENT ACROSS BASIN WITH SCATTEROMETER AND BUOY OBS SHOWING 
MODERATE TRADES E OF 80W AND FRESH TRADES NEAR COAST OF COLOMBIA 
WHERE SEAS ESTIMATED AT NEAR 7 FT. BUOY 42058 NEAR 15N75W STEADY 
AT 5 FT. TWO TROPICAL WAVES CONTINUE TO MOVE THROUGH THE BASIN. 
A WEAK WAVE ALONG 82W BECOMING ILL-DEFINED...WHILE A SECOND WAVE 
ALONG 71W INTERACTING WITH AN UPPER LOW BETWEEN THE BAHAMAS AND 
PUERTO RICO IS TRIGGERING WIDESPREAD SHOWERS E-NE OF WAVE AXIS. 
FAVORABLE CONDITIONS ALOFT FOR CONVECTION EXPECTED TO CONTINUE 
BEHIND WAVE ACROSS HISPANIOLA TODAY. FIRST WAVE WILL MOVE INTO 
CENTRAL AMERICA THU...ABSORBED BY A LARGER MONSOON CIRCULATION. 
SECOND WAVE EXPECTED TO MOVE SLOWLY W ACROSS CENTRAL AND WESTERN 
CARIBBEAN THROUGH FRI. MODEL GUIDANCE SHOWS N PORTION OF WAVE 
SPLITTING OFF NEAR CENTRAL CUBA AND BAHAMAS FRI WHILE S PORTION 
BECOMES LATEST VICTIM OF EAST PAC MONSOON CIRCULATION DEVELOPING 
EASTWARD ACROSS SW CARIBBEAN. TRADES WILL INCREASE BEHIND SECOND 
WAVE AND RETURN TO NEAR-NORMAL CONDITIONS NEAR COLOMBIA BY FRI.

HIGH-AMPLITUDE TROPICAL WAVE IN WEST-CENTRAL ATLC MOVING QUICKLY 
AROUND 20 KT...BEST DEFINED AT H7...IS EXPECTED TO MOVE INTO THE 
TROPICAL N ATLC WATERS EARLY FRI THE ACROSS THE LESSER ANTILLES 
BY SAT MORNING. GFS DEPICTING 20-25 KT E TO SE WINDS BEHIND WAVE 
AXIS S OF 15N...AND AT THIS 20 KT TRANSLATION SPEED CREATES A 
POSSIBLE TRAPPED FETCH SCENARIO. WAVE MODEL BUILDS SEAS TO 7-10 
FT BEHIND WAVE BY 48-72 HRS, WHICH APPEARS A REASONABLE SOLUTION.

...SW N ATLANTIC W OF 55W INCLUDING THE BAHAMAS...               
MODEL PREFERENCE: BLEND OF PREVIOUS OFFICIAL FORECAST WITH 
GFS/ECMWF FOR MARINE WINDS AND WW3/NWPS FOR SEA HEIGHTS. HIGH 
CONFIDENCE BASED ON PERSISTENCE AND GOOD AGREEMENT OF MODELS.

WEAK W ATLC RIDGE ALONG 29-30N EXTENDING INTO N FLORIDA...WITH 
LIGHT TO MODERATE WINDS ACROSS MOST OF THE AREA...AND TRADES 15 
TO LOCALLY 20 KT S OF 23N E OF 74W. CONVECTION ASSOCIATED WITH 
INTERACTION BETWEEN TROPICAL WAVE ALONG 71W AND UPPER LOW WILL 
MOVE WNW ACROSS HISPANIOLA INTO SOUTHERN WATERS THROUGH TONIGHT. 
OTHERWISE...RIDGE WILL BE FORCED SOUTHWARD BY WEAK COLD FRONT 
MOVING OFF CAROLINAS COAST THU NIGHT WITH INCREASE IN SOUTHERLY 
FLOW W OF 77W AS TAIL END OF COLD FRONT APPROACHES 31N W OF 76W 
SAT AND SUN. A SLIGHT INCREASE IN WINDS AND SEAS S OF 22N WILL 
BE SEEN ACROSS SE PORTIONS BEHIND E CARIB WAVE AND THEN AGAIN 
AHEAD AND BEHIND NEXT WAVE ENTERING TROPICAL N ATLC WATERS FRI.

$$
.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 MUNDELL. NATIONAL HURRICANE CENTER.