Marine Interpretation Message
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000
AGXX40 KNHC 251812
MIMATS

MARINE WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
212 PM EDT THU AUG 25 2016

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: GLOBAL MODEL CONSENSUS. HIGH CONFIDENCE THROUGH
SAT...THEN LOW CONFIDENCE SUN-MON.

A RIDGE AXIS THAT EXTENDS ACROSS THE SOUTHEASTERN UNITED STATES TO
THE TEXAS GULF COAST WILL SLOWLY DRIFT NORTHWESTWARD THROUGH THE
END OF THE WEEK. MODERATE TO FRESH EASTERLY WINDS WILL OCCUR OVER
THE NORTHEASTERN GULF THROUGH TONIGHT...WITH MAINLY GENTLE TO
MODERATE WINDS ELSEWHERE OVER THE GULF. SEAS OF 2 TO 3 FEET WILL
DOMINATE THE BASIN...EXCEPT THE NORTHEASTERN GULF WHERE 3 TO 5 FT
SEAS ARE FORECAST THROUGH TONIGHT. AS THE RIDGE AXIS SLIDES
NORTHWEST SATURDAY THROUGH SATURDAY NIGHT...THE GENTLE TO MODERATE
WINDS AND SEAS OF 2 TO 3 FEET WILL EXPAND TO INCLUDE THE
NORTHEASTERN GULF.

BEYOND SATURDAY NIGHT THERE IS A HIGH AMOUNT OF UNCERTAINTY AS TO
WHAT WILL EVENTUALLY OCCUR WITH A TROPICAL LOW CURRENTLY NEAR
21N72W. MODELS ARE IN DISAGREEMENT ON THE POTENTIAL DEVELOPMENT OF
THIS SYSTEM AS IT REACHES THE SOUTHEASTERN GULF SUNDAY OR MONDAY.
THEREFORE...THIS PORTION OF THE FORECAST IS LOW CONFIDENCE.
FOR THE 1200 UTC FORECAST PACKAGE USED BLENDED GLOBAL MODELS
WEIGHTED FOR THIS PORTION OF THE FORECAST...INDICATING 20 TO 30
KT WINDS AND SEAS TO 8 FT OVER THE EASTERN GULF SUNDAY NIGHT
THROUGH TUESDAY.

...CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN
55W AND 64W...

MODEL PREFERENCE: GLOBAL MODEL CONSENSUS. HIGH CONFIDENCE.

LOWER PRESSURE NORTH AND NORTHEAST OF THE AREA...ASSOCIATED WITH
AN AREA OF LOW PRESSURE CENTERED NW OF PUERTO RICO AND TS GASTON
IN THE CENTRAL ATLANTIC...IS KEEPING A WEAK PRESSURE GRADIENT
ACROSS THE REGION COMPARED TO THE LAST SEVERAL WEEKS. MAINLY
GENTLE TO MODERATE TRADE WINDS WILL PREVAIL OVER THE WESTERN
CARIBBEAN THROUGH THE FORECAST PERIOD. MODERATE TO LOCALLY FRESH
TRADE WINDS ARE FORECAST OVER THE CENTRAL AND EASTERN CARIBBEAN
THROUGH SUNDAY. RIDGING WILL BUILD OVER THE CENTRAL AND WESTERN
ATLANTIC BY EARLY NEXT WEEK WHICH WILL BRING FRESH TO LOCALLY
STRONG WINDS BACK TO THE SOUTH- CENTRAL CARIBBEAN...INCLUDING
NORTHWEST OF THE COAST OF COLOMBIA. ELSEWHERE...LONG PERIOD N-NE
SWELL GENERATED BY GASTON IS EXPECTED TO PROPAGATE INTO THE
TROPICAL WATERS N OF 18N E OF 57W FRI.

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

MODEL PREFERENCE: GLOBAL MODEL CONSENSUS. LOW CONFIDENCE.

A DISSIPATING STATIONARY FRONT AND TROUGH WILL SUPPORT SHOWERS
AND THUNDERSTORMS ACROSS THE NORTHWESTERN ZONES THE NEXT COUPLE
OF DAYS. THE MAIN FORECAST ISSUE THROUGH THE WEEKEND IS WHAT WILL
EVENTUALLY OCCUR WITH A TROPICAL LOW CURRENTLY TRACKING WEST TO
WEST-NORTHWEST FROM NEAR 21N72W. GLOBAL MODELS ARE DIVERGENT ON
WHETHER THIS SYSTEM WILL DEVELOP...WHICH MAKES THE CURRENT
FORECAST LOW CONFIDENCE. LATEST SCATTEROMETER DATA INDICATE THAT
THE GALE THAT WAS PREVIOUSLY OCCURRING THE PAST 24 HOURS IS LIKELY
ENDING SOON. BASED ON UNCERTAINTIES IN THE MODELS AND THE LATEST
DATA...THIS FORECAST PACKAGE ENDS THE GALE BY 0600 UTC
TONIGHT...AND TAKES THE LOW ACROSS THE SOUTHEASTERN THEN CENTRAL
BAHAMAS THROUGH SATURDAY WITH WINDS AROUND 20 TO 30 KT MAINLY TO
THE NORTH AND EAST OF THE LOW. SEAS EAST OF THE BAHAMAS MAINLY
BETWEEN 8 TO 12 FT CAN BE EXPECTED WITH THE LONG FETCH OF 20 TO 30
KT WINDS. SEAS IN THE PROTECTED AREAS OF THE BAHAMAS WITH THE 20
TO 30 KT WINDS ARE FORECAST FOR THE MOST PART TO REMAIN BELOW 8
FT. HOWEVER...SINCE THIS PORTION OF THE FORECAST IS LOW
CONFIDENCE...ANY MAJOR CHANGE WITH THIS SYSTEM WOULD RESULT IN
LARGE SHIFTS IN THE FORECAST.

ELSEWHERE...LARGE SWELL ASSOCIATED WITH GASTON WILL REACH
FORECAST WATERS BETWEEN 55-60W FRI NIGHT AND CONTINUE THROUGH THE
WEEKEND...TO AFFECT ZONE AMZ115 SUN NIGHT AND MON.

$$

.WARNINGS...ANY CHANGES IMPACTING COASTAL NWS OFFICES WILL BE
COORDINATED THROUGH AWIPS II COLLABORATION CHAT OR BY TELEPHONE:

.GULF OF MEXICO...
     NONE.

.CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN
55W AND 64W...
     NONE.

.SW N ATLANTIC INCLUDING THE BAHAMAS...
.AMZ117...BAHAMAS INCLUDING CAY SAL BANK...
     GALE WARNING TODAY INTO TONIGHT.
.AMZ119...ATLANTIC FROM 22N TO 27N E OF BAHAMAS TO 70W...
     GALE WARNING TODAY.
.AMZ123...ATLANTIC S OF 22N W OF 70W INCLUDING APPROACHES TO THE
WINDWARD PASSAGE...
     GALE WARNING TODAY INTO TONIGHT.

$$

*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.HURRICANE WARNINGS.GOV/MARINE

$$

.FORECASTER LATTO. NATIONAL HURRICANE CENTER.



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