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000
AGXX40 KNHC 260800 AAA
MIMATS

MARINE WEATHER DISCUSSION...UPDATED
NWS NATIONAL HURRICANE CENTER MIAMI FL
400 AM EDT SUN MAY 26 2013

UPDATED FOR PREFERENCE IN SW N ATLC

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: HIGH CONFIDENCE IN GFS AND MWW3 BLENDED WITH
PREVIOUS OFFICIAL FORECAST THROUGH LATE MON...THEN A BLEND THE
GFS/MWW3 WITH THE ECMWF/EC WAVE TUE THROUGH THU WITH MEDIUM
CONFIDENCE.

HIGH PRESSURE FROM THE NORTHEAST TO SOUTHWEST GULF WILL MOVE TO
ALONG THE NORTHERN GULF COASTAL PLAIN BY MON BEFORE SHIFTING SOUTH
AGAIN IN THE WESTERN GULF WED AND THU. A BLEND OF THE 00Z MWW3
AND PREVIOUS FORECAST WAS USED TO ADJUST THE SEAS THROUGH MON.
FROM MON NIGHT THROUGH WED...AN UPPER TROUGH IS EXPECTED TO DIG
SOUTHWARD THROUGH THE EASTERN GULF AND MOVE INTO FLORIDA. THE 00Z
ECMWF DIGS A DEEPER H2 TROUGH THAN THE SIMILAR GFS AND UKMET
SOLUTIONS. AT THE SURFACE...THE 00Z MODELS AGREE ON BUILDING A
TROUGH OFF THE W COAST OF FLORIDA ON TUE...SHIFTING IT E OF
FLORIDA ON THU. THE GFS BUILDS 25 KT WINDS IN THE STRAITS OF
FLORIDA ON TUE. THESE WINDS ARE STRONGER THAN ANY OF THE OTHER
MODELS...LOWERING CONFIDENCE IN THE GFS SOLUTION AT THIS POINT AND
INTO THU AS IT REMAINS A STRONGER SOLUTION THAN THE CONSENSUS. A
50/50 BLEND OF THE GFS AND ECMWF WITH THE PREVIOUS FORECAST WILL
BE USED TO ADJUST THE WIND GRIDS. THE EC WAVE AND MWW3 BOTH BUILD
SEAS TO 8 FT OVER THE E CENTRAL GULF BY WED AFTERNOON UNDER A
LARGE SWATH OF FRESH ENE WINDS STRETCHING FROM THE FL KEYS TO SE
LOUISIANA. GIVEN THE DIFFERENCES IN THEIR WIND FIELDS...WILL KEEP
WITH THE 50/50 EC AND MWW3 BLEND FOR SEAS.

...CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN
55W AND 64W...
MODEL PREFERENCE: MEDIUM CONFIDENCE IN ECMWF AND EC WAVE BLENDED
WITH PREVIOUS OFFICIAL FORECAST THROUGH LATE MON...THEN A BLEND OF
THE PREVIOUS FORECAST WITH THE GFS AND MMW3 TUE THROUGH THU WITH
MEDIUM CONFIDENCE.

THE MODELS QUICKLY DIVERGE WITH THE WINDS AND SEAS OFF THE COAST
OF COLOMBIA BY EARLY MON MORNING...WITH THE 00Z ECMWF AND UKMET
SUPPORTING A LARGER AREA OF FRESH TO STRONG TRADES THAN THE 00Z
GFS. THE ALTIMETER PASS FROM AROUND 22Z SHOWED SEAS WERE ALREADY
NEAR 8 FT ALONG THE COAST OF COLOMBIA UNDER PERSISTENT FRESH
TRADES. THE EC WAVE SEEMS TO HAVE A SLIGHT ADVANTAGE HERE AND THE
ECMWF HAS THE SUPPORT OF THE UKMET EARLY IN THE PERIOD. STARTING
TUE...AN UPPER TROUGH DIGGING OVER THE EASTERN GULF OF MEXICO
WILL INCREASE TROUGHING OVER THE NW CARIBBEAN. BY WED...THE 00Z
GFS BUILDS A LARGER AREA OF FRESH EASTERLY WINDS ACROSS THE
CENTRAL AND WESTERN CARIBBEAN ALONG 16N COMPARED TO THE ECMWF
WHICH BUILDS A LARGER CIRCULATION OF LIGHT TO GENTLE WINDS AROUND
LOW PRESSURE IN THE SW CARIBBEAN. THE UKMET HAS TRENDED TOWARD THE
GFS SOLUTION HERE. WILL RELY MORE HEAVILY ON THE GFS FORECAST HERE
ON TUE THROUGH THU TO FALL IN LINE WITH THE CONSENSUS. THE UKMET
WAVE CARRIES SLIGHTLY HIGHER SEAS THAN THE MWW3 ON WED AND THU
ACROSS MUCH OF THE CARIBBEAN...WITH BOTH MODELS AROUND 2 FT HIGHER
THAN THE ECMWF. THE MWW3 LOOKS LIKE A GOOD COMPROMISE ON WED AND
THU.

...SW N ATLANTIC INCLUDING THE BAHAMAS...
MODEL PREFERENCE: HIGH CONFIDENCE IN GFS AND MWW3 BLENDED WITH
PREVIOUS OFFICIAL FORECAST THROUGH LATE MON...THEN A BLEND THAT
INCLUDES THE ECMWF AND...TO A LESSER EXTENT...THE EC WAVE TUE
THROUGH THU WITH MEDIUM CONFIDENCE.

WINDS AND SEAS ARE EXPECTED TO REMAIN BELOW ADVISORY CRITERIA IN
THE SW N ATLC THROUGH WED. HOWEVER...BOTH WINDS AND SEAS WILL
BUILD OVER THE BAHAMAS BY THU IN RESPONSE TO A SURFACE TROUGH
BUILDING OVER FLORIDA ASSOCIATED WITH AN UPPER TROUGH DIGGING
THROUGH THE EASTERN GULF OF MEXICO LATE MON AND TUE AND SETTLING
BETWEEN FLORIDA AND THE BAHAMAS WED AND THU. THE 00Z GFS AND
ECMWF BOTH AGREE ON THE ONSET OF 25 KT WINDS ALONG THE N COAST OF
HAITI BY 00Z TUE...BUT THE GFS IS MORE AGGRESSIVE AS IT SPREADS
FRESH TO STRONG EASTERLIES WESTWARD ALONG THE N COAST OF CUBA AND
INTO THE STRAITS OF FLORIDA THROUGH TUE NIGHT WHILE THE 00Z ECMWF
IS GENERALLY WEAKER WITH THE WINDS AND CARRIES A WEAKER SURFACE
TROUGH. THESE DIFFERENCES CONTINUE INTO WED AND THU...WITH THE
GFS BUILDING WINDS S OF ANDROS ISLAND TO 30 KT WHILE THE 00Z
ECMWF HAS A MUCH SMALLER AREA OF 25 KT WINDS. THE UKMET LOOKS MORE
LIKE A COMPROMISE OF THESE SOLUTIONS...CAPPING WINDS AT 25 KT. A
50/50 BLEND OF THE ECMWF AND GFS WILL BE USED TO ADJUST THE
FORECAST TUE THROUGH THU. THE MWW3 AND UKMET BUILD SEAS TO 8 FT
WED WHILE THE LOWER RESOLUTION EC WAVE CAPS SEAS AT 7 FT THROUGH
THU. WILL SIDE SLIGHTLY MORE WITH THE HIGHER SEAS SEEN IN THE MWW3
WHEN BLENDING WITH THE PREVIOUS FORECAST TUE THROUGH THU.

$$
.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 SCHAUER. NATIONAL HURRICANE CENTER.