000
AGXX40 KNHC 011825
MIMATS

MARINE WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
225 PM EDT WED MAY 1 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 THROUGH
THE EARLY PART OF THE FORECAST...THEN LOW CONFIDENCE DURING THE
WEEKEND DUE TO UNCERTAINTY IN TRACK/STRENGTH ASSOCIATED WITH LOW
PRES FORMING IN THE CENTRAL GULF.

A MID TO UPPER LEVEL TROUGH ASSOCIATED WITH AN UPPER LEVEL LOW
OVER FAR E TEXAS IS MAINTAINING A SURFACE TROUGH OVER THE CENTRAL
GULF WATERS AS INDICATED BY LATEST OBSERVATIONS. SHORTWAVE TROUGH
MOVING THROUGH THE UPPER CIRCULATION HELPED PRODUCE A LARGE MCS
OVER THE CENTRAL GULF WATERS OVERNIGHT. THE MCS HAS MOVED ACROSS
THE SE GULF OF MEXICO THROUGH TODAY. THOUGH IT WEAKENED
SOMEWHAT...ACTIVE CONVECTION REMAINED AS IT HAS REACHED THE
FLORIDA KEYS AND THE SW COAST OF FLORIDA THIS AFTERNOON. LATEST
OBSERVATIONS INDICATE GENTLE TO MODERATE WINDS WITH SEAS 4 FT OR
LESS PREVAIL OVER THE FORECAST AREA. THE MID/UPPER LEVEL LOW WILL
SPIN DOWN OVER THE NEXT 24 HOURS AS IT SLOWLY MOVES EASTWARD AS A
MAJOR DISTURBANCE MOVES THROUGH THE CENTRAL PLAINS AND MISSISSIPPI
VALLEY OVER THE NEXT COUPLE OF DAYS. MODELS ARE IN GOOD AGREEMENT
REGARDING THE TIMING OF AN ASSOCIATED COLD FRONT MOVING OFF THE
TEXAS COAST BY THU AFTERNOON. GALE FORCE WINDS ARE EXPECTED BEHIND
THE FRONT ON FRI MORNING OFF THE COAST OF TAMAULIPAS IN GMZ017
EARLY FRI. ELSEWHERE...THERE IS A CONSENSUS IN THE MODELS
CONCERNING THE DEVELOPMENT OF A LOW IN THE GULF LATER IN THE
WEEK. THERE REMAINS SOME DISAGREEMENT ON THE TRACK AND STRENGTH
OF THE LOW OVER THE WEEKEND...THOUGH THERE IS MORE AGREEMENT THAT
IS THAT THE AREA OF LOW PRESSURE WILL REACH FLORIDA BY
SUN...EITHER IN THE FORM OF A LOW PRESSURE CENTER OR A TROUGH.

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

CURRENT OBSERVATIONS INDICATE GENTLE TO MODERATE TRADES PREVAIL
ACROSS THE FORECAST AREA...EXCEPT TO FRESH ACROSS THE GULF OF
HONDURAS. SEAS ARE GENERALLY IN THE 4-6 FT RANGE. WITH ONLY WEAK
HIGH PRESSURE N OF REGION...A LOOSE PRESSURE GRADIENT WILL
PREVAIL. THIS WILL MAINTAIN GENTLE TO MODERATE TRADEWIND FLOW
ACROSS THE AREA THROUGH THE FORECAST PERIOD. WITH THIS WIND
FLOW...SEAS WILL GENERALLY REMAIN BELOW 6 FT THROUGH THE FORECAST
PERIOD OVER THE TROPICAL N ATLC AND SEAS SUBSIDING TO 4 FT OR
BELOW BY FRI OVER THE CARIBBEAN WATERS.

...SW N ATLANTIC INCLUDING THE BAHAMAS...
MODEL PREFERENCE: GFS/ECMWF BLEND WITH AVERAGE CONFIDENCE.

LATEST SATELLITE OBSERVATIONS INDICATE THAT THE WEAK LOW PRESSURE
CENTER NEAR 31N75W THIS MORNING HAS WEAKENED INTO A TROUGH. LIGHT
TO GENTLE WINDS PREVAIL OVER MOST OF THE FORECAST AREA...EXCEPT
TO FRESH N OF 30N WITHIN 90 NM OF THE TROUGH AXIS. SEAS TO 8 FT
STILL REMAIN N OF 30N WITHIN THE AREA OF FRESH WINDS NEAR THE
TROUGH. OTHERWISE...SEAS IN THE 5-6 FT RANGE PREVAIL E OF THE
BAHAMAS...AND 1-2 FT W OF THE BAHAMAS. THE COMBINATION OF HIGH
PRESSURE BUILDING N OF THE AREA AND LOW PRESSURE OVER THE GULF
WATERS WILL RESULT IN A TIGHT PRESSURE GRADIENT OVER THE NW PART
OF THE FORECAST AREA BY THU. THIS WILL STRENGTHEN WINDS OVER THIS
AREA WITH SEAS BUILDING TO 10 FT BY THU AFTERNOON. LOW PRESSURE
WILL DEVELOP WITHIN THE TROUGH OVER THE CENTRAL GULF WATERS BY
FRI. THOUGH THERE ARE SOME MODEL DIFFERENCES WITH REGARD TO THE
TRACK AND CHARACTER OF THE LOW PRES IN THE GULF...THE PATTERN
CHANGES LITTLE FOR SW N ATLC ZONES. AS A RESULT THE FRESH TO
STRONG WINDS AND SEAS 8 FT OR GREATER WILL PREVAIL AFTER THU
THROUGH MUCH...IF NOT ALL...OF THE FORECAST PERIOD. MODERATE WINDS
AND SEAS WILL PREVAIL OVER THE REMAINDER OF THE FORECAST AREA.

.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 AL. NATIONAL HURRICANE CENTER.