000
AGXX40 KNHC 171846
MIMATS

MARINE WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
245 PM EDT THU OCT 17 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 AND MWW3 BLENDED WITH PREVIOUS OFFICIAL 
FORECAST WITH HIGH CONFIDENCE.

HIGH PRES OF 1016 MB THAT WAS OVER THE N CENTRAL GULF THIS 
MORNING HAS SHIFTED ESE TO NEAR 26N87W...WHILE A COLD FRONT THAT 
ENTERED THE FAR NW GULF WED AFTERNOON EXTENDS FROM MOBILE 
ALABAMA SW TO 26N94W TO INLAND MEXICO AT 24N98W. THE CURRENT AND 
LATEST BUOY OBSERVATIONS SHOW LIGHT TO GENTLE WINDS ACROSS THE 
AREA TO THE E OF THE FRONT...WHILE N-NE WINDS OF 15-20 KT ARE 
NOW EVIDENT TO THE W OF FRONT. THE OBSERVATIONS SHOW LOW SEAS IN 
THE RANGE OF 1-2 FT E OF THE FRONT...AND 3-4 FT SEAS BEHIND THE 
FRONT. THE FRONT IS FORECAST TO REACH FROM NEAR THE EXTREME 
WESTERN FLORIDA PANHANDLE TO THE FAR WESTERN GULF THIS 
EVENING....THEN BECOME STATIONARY FROM THE FLORIDA PANHANDLE TO 
THE WESTERN GULF FRI PER MODEL CONSENSUS. A REINFORCING SURGE OF 
NORTHERLY FLOW FROM BUILDING HIGH PRES WILL ALLOW THE FRONT TO 
BRIEFLY PUSH S AGAIN ON SAT MAINLY OVER THE EASTERN GULF...AND 
BEGIN TO LIFT BACK N AS WARM FRONT OVER THE WESTERN ON FRI 
AFTERNOON AND INTO SAT. THE EASTERN PORTION OF THE FRONT THAN 
LOSES ALL OF ITS UPPER SUPPORT AND TRANSITIONS TO A WEAKENING 
STATIONARY DURING SAT SUN. THE REINFORCING NORTHERLY SURGE DOES 
NOT APPEAR TO BE AS STRONG AS EARLIER FORECAST GFS RUNS HAD 
INDICATED WITH THE SURGED EXPECTED TO BE N-NE IN THE 15-20 KT 
RANGE WITH SEAS BUILDING TO AROUND 5 OF 6 FT IN THE FAR WESTERN 
GULF. THESE WINDS WILL BE SHORT-LIVED AS THE HIGH PRESSURE TO 
THE N OF THE AREA WILL BE RATHER WEAK AS IT QUICKLY SLIDES OFF 
TO THE NE INTO EARLY NEXT WEEK. ASIDE FROM THE BRIEF INCREASE IN 
WINDS AND SEAS EXPECTED IN THE FAR WESTERN GULF...WINDS AND SEAS 
ELSEWHERE WILL CHANGE LITTLE UNDER A CONTINUING WEAK PRES 
PATTERN THROUGH DAY 5. 

...CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN
55W AND 65W...

MODEL PREFERENCE: GFS AND MWW3 BLENDED WITH PREVIOUS OFFICIAL 
FORECAST WITH HIGH CONFIDENCE.

A WEAK PRESSURE GRADIENT ASSOCIATED WITH BROAD TROUGH STRETCHING 
FROM W OF BERMUDA ACROSS THE BAHAMAS AND CUBA...AND INTO THE 
WESTERN CARIBBEAN CONTINUES TO MAINTAIN RATHER BENIGN MARINE 
CONDITIONS OVER THE AREA AS NOTED IN THE LATEST AND CURRENT BUOY 
OBSERVATIONS THROUGHOUT. PARTIAL ASCAT DATA FROM THIS MORNING 
VERIFIED THESE CONDITIONS AS WELL. THE ONLY WORTH NOTING MARINE 
ISSUE WILL BE NE SWELLS PRODUCING SEAS OF 4-6 FT THROUGH THE 
TROPICAL N ATLC ZONES. THESE SWELLS WILL GRADUALLY SUBSIDE TO 
AROUND 5 FT FRI...BUT ARE EXPECTED TO BUILD AGAIN BEGINNING SAT 
ACROSS THE EASTERN AND CENTRAL PORTIONS OF THE TROPICAL N ATLC 
AS ANOTHER SET OF SWELLS FROM THE CENTRAL ATLC ARRIVES. 
WAVEWATCH GUIDANCE SUGGESTS THAT THESE WILL LINGER INTO EARLY 
NEXT WEEK. 

...SW N ATLANTIC INCLUDING THE BAHAMAS...

MODEL PREFERENCE: GFS AND MWW3 BLENDED WITH PREVIOUS OFFICIAL 
FORECAST WITH HIGH CONFIDENCE.

A WEAK PRESSURE GRADIENT ASSOCIATED WITH BROAD TROUGHING ACROSS 
THE REGION WILL MAINTAIN GENTLE TO MODERATE WINDS AND LOW SEAS 
THROUGH TUE. A WEAK COLD FRONT IS EXPECETD TO MOVE INTO THE NW 
PORTION ON SAT...THEN SLOW DOWN ITS FORWARD PROGRESS IT BECOMES 
STATIONARY ACROSS THE NW PORTION INTO MON. THE FRONT WILL THEN 
LIFT BACK N AS A WARM FRONT LATE MON AND TUE AS A WEAK TROUGH 
LINGERS OVER THE SW WATERS AND NEAR THE BAHAMAS. WINDS AND SEAS 
MAY BE HIGHER IN AND NEAR TSTM ACTIVITY OVER THE EASTERN PORTION 
THROUGH SAT.

$$

.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 AGUIRRE. NATIONAL HURRICANE CENTER.