000
AGXX40 KNHC 301913
MIMATS

MARINE WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
313 PM EDT TUE APR 30 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 MODELS WITH AVERAGE CONFIDENCE.
SECTORIZED GFS IN WESTERN GULF TO CAPTURE HIGHER WINDS BEHIND
FRONT.

DEEP LAYER TROUGH SUPPORTS SURFACE STATIONARY TROUGH FROM 29N95W
TO 25N95W THROUGH THU.  NUMEROUS MODERATE TO STRONG CONVECTION
WITHIN 150 NM E OF TROUGH WITH HIGHER WIND AND SEAS NEAR TSTMS.

WEAK COLD FRONT PUSH OFF TEXAS COAST LATE THU BRINGING STRONG TO
NEAR GALE FORCE WINDS AND 8-9 FT SEAS ALONG TEXAS COAST FRI. 
GOOD AGREEMENT IN GUIDANCE IN TIMING...LESS CERTAINTY IN REACHING
GALE FORCE ALONG COAST OF MEXICO FRI. IT REMAINS MAIN FORECAST
CHALLENGE. FORECAST BRINGS GALE CONDITIONS EXPECTED FOR GMZ017
WITH GMZ023 A BIGGER QUESTION MARK. ADJUSTED WINDS FORCE UPWARD
OVER NW GULF CLOSER TO UKMET THU NIGHT AND FRI.
MEANWHILE...OFFSHORE FLOW CONTINUES TO DELIVER AREAS OF SMOKE FROM
FOREST FIRES LIMITING VISIBILITIES ALONG CAMPECHE COAST BELOW 5
NM. FOR SAT... FRONT WEAKENS AS IT SHIFTS FARTHER SE AND WASHES
OUT BY LATE SAT FROM FLORIDA BIG BEND TO CENTRAL GULF. WINDS AND
SEAS DIMINISH ACCORDINGLY AS HIGH PRES BUILDS BEHIND FRONT OVER NW
GULF.

...CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN
55W AND 64W...
MODEL PREFERENCE: GFS/ECMWF/PERSISTENCE BLEND WITH GOOD
CONFIDENCE.

HIGH PRES N OF REGION MAINTAIN MODERATE TO FRESH BREEZES ACROSS
TROPICAL N ATLC AND CENTRAL CARIBBEAN WITH GENTLE TO MODERATE E
FLOW THROUGH MID WEEK...EXCEPT FRESH BREEZES EXPECTED ACROSS GULF
OF HONDURAS TUE THROUGH THU AND ALONG COAST OF COLOMBIA. LONG
PERIOD NE SWELL 6 FT SEEP THROUGH ATLC PASSAGES TONIGHT THEN
BEGINNING SUBSIDING THROUGH WED. WINDS DIMINISH ACROSS BASIN LATER
IN THE WEEK AS HIGH PRES N OF AREA SHIFTS E AND REPLACED BY WEAK
LOW PRES TROUGH...WEAKENING PRES GRADIENT OVER REGION.

...SW N ATLANTIC INCLUDING THE BAHAMAS...
MODEL PREFERENCE: GFS/ECMWF BLEND WITH AVERAGE CONFIDENCE THROUGH
WEAK AND LOW CONFIDENCE LATE IN PERIOD DUE TO LOW PRES TROUGH
POSTN.

WEAK HIGH PRES CENTER W OF BERMUDA SHIFT E AHEAD OF WEAK LOW PRES
DEVELOPING OVER CAROLINAS SHIFTING SE INTO DISCUSSION AREA.
GFS/ECMWF/UKMET ARE IN GOOD AGREEMENT SHOWING LOW PRES FORMING AND
DRIFTING INTO BASIN WED...BEFORE OPENING INTO TROUGH LATE WED.
NOT GOOD AGREEMENT AMONG MODELS ABOUT POSTN...TIMING AND STRENGTH
OF LOW PRES/TROUGH BY WEEKEND. KEPT GFS/ECMWF BLEND FOR NOW.

.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...GALE CONDITIONS EXPECTED FRI.
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.