000
AGXX40 KNHC 181829
MIMATS

MARINE WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
229 PM EDT SAT MAY 18 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...GFS BLENDED WITH NAM80 AND OFFICIAL FORECAST
WITH HIGH CONFIDENCE.

A RIDGE EXTENDS FROM THE WESTERN ATLC ACROSS THE NORTHERN GULF
COAST. SCATTEROMETER AND BUOY REPORTS INDICATE GENERALLY LIGHT TO
MODERATE E TO SE FLOW ACROSS THE GULF THIS AFTERNOON. WINDS ARE
SLIGHTLY HIGHER OVER THE NW GULF...BETWEEN THE HIGH PRES TO THE
EAST AND PERSISTENT TROUGHING OVER TEXAS. SEAS ARE RUNNING 3 TO 5
FT OVER THE WESTERN GULF AND 1 TO 3 FT OVER THE EASTERN
GULF...EXCEPT SLIGHTLY HIGHER IN THE STRAITS OF FLORIDA WHERE
EASTERLY FLOW IS COUNTER THE FLORIDA CURRENT. LITTLE CHANGE IS
ANTICIPATED THROUGH THE MIDDLE OF NEXT WEEK. FORECAST DATABASE IS
A BLEND OF GFS AND NAM80 THROUGH 48 HOURS TO CAPTURE THE LOCAL
EFFECTS OVER THE WESTERN GULF...PRIMARILY THE ENHANCED FLOW IN THE
LATE EVENING OVER THE EASTERN BAY OF CAMPECHE...AND A BLEND OF GFS
AND OFFICIAL ALONE BEYOND 48 HOURS.

...CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN
55W AND 64W... MODEL PREFERENCE: GFS BLEND WITH OFFICIAL FORECAST
WITH HIGH CONFIDENCE.

THE OVERALL PATTERN CONTINUES TO BE INFLUENCED BY HIGH PRES WELL N
OF THE AREA PARKED BETWEEN N FLORIDA AND BERMUDA...MAINTAIN
MODERATE TO FRESH TRADE WINDS OVER MUCH OF THE EASTERN AND CENTRAL
CARIBBEAN...AND LIGHT TO MODERATE WINDS ELSEWHERE. SCATTEROMETER
DATA FROM THIS MORNING CONFIRMED PERSISTENT 20 TO 25 KT WINDS OFF
THE COAST OF COLOMBIA THIS MORNING. IN ADDITION TO THE INFLUENCE
OF THE RIDGE TO THE NORTH...THIS FLOW IS EXHIBITING A DIURNAL
ENHANCEMENT...ALLOWING WINDS TO PEAK TO 25 KT IN THE EARLY
MORNING. A LOW LATITUDE/LOW AMPLITUDE TROPICAL WAVE IS MIGRATING
WESTWARD THROUGH NE SOUTH AMERICA. CONTINUITY AND THE RECENT
SATELLITE PRESENTATION HAS BEEN RELATIVELY GOOD...AND THIS
MORNINGS SOUNDING FROM CAYENNE FRENCH GUIANA INDICATED THE WAVE
HAD RECENTLY PASSED. THE MAIN IMPACT ON SENSIBLE WEATHER WILL BE A
SLIGHT ENHANCEMENT OF E WINDS OVER THE SE CARIBBEAN THROUGH MON.
THE WAVE WILL LIKELY GET HARDER TO TRACK AS IT SHIFTS FARTHER W
INTO SOUTH AMERICA AND AWAY FROM ITS SUPPORTING EASTERLY FLOW OVER
THE ATLC. LOOKING AHEAD...THE HIGH PRES TO THE N WILL WEAKEN
ENOUGH BY TUE TO ALLOW WINDS TO REMAIN AT OR BELOW 20 KT OFF
COLOMBIA DESPITE THE APPROACH OF THE TROPICAL WAVE...WHICH MAY
HAVE LARGELY DAMPENED OUT BY THEN. STRONGER HIGH PRES REBUILDS BY
MIDWEEK OVER THE CENTRAL ATLC...ALLOWING A RESURGENCE IN TRADE
WIND FLOW OVER THE TROPICAL N ATLC INTO THE EASTERN CARIBBEAN.

...SW N ATLANTIC INCLUDING THE BAHAMAS... 
MODEL PREFERENCE: GFS BLEND WITH OFFICIAL FORECAST WITH HIGH
CONFIDENCE.

A 1023 MB HIGH PRES IS CENTERED NEAR 31N73W...MAINTAINING LIGHT TO
MODERATE FLOW N OF 25N...AND MODERATE TO FRESH TRADES S OF 25N.
BUOY AND CRYOSAT ALTIMETER DATA INDICATE SEAS OF 3 TO 5 FT OUTSIDE
THE BAHAMAS. THE MAIN ISSUE WILL BE THE ADVANCE OF A LATE SEASON
COLD FRONT MOVING THROUGH BERMUDA AND SHIFTING MAINLY TO THE EAST
OF 65W THROUGH 48 HOURS. THE HIGH PRES WILL DISSIPATE AS THE FRONT
DRIVES SE...FOLLOWED BY SLIGHTLY STRONGER HIGH PRES BY EARLY TUE
CENTERED NEAR 31N60W. LITTLE CHANGE IS EXPECTED IN THE SENSIBLE
WEATHER ACROSS THE DISCUSSION AREA ACCORDINGLY...WITH WINDS S OF
25N DIMINISHING SLIGHTLY THROUGH MON...THEN INCREASING AGAIN
THROUGH MID WEEK N OF THE ISLANDS.

.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.