Marine Interpretation Message
Issued by NWS

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000
AGXX40 KNHC 200800
MIMATS

MARINE WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
400 AM EDT SUN APR 20 2014

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: LATEST GFS BLENDED WITH PREVIOUS OFFICIAL. FOR
WAVES USED A BLEND OF THE LATEST MWW3 ALONG WITH NWPS PARAMETERS
WITH PREVIOUS FORECAST. HIGH CONFIDENCE.

HIGH PRES HAS SETTLED IN ACROSS THE AREA PER LATEST SURFACE
ANALYSIS WHERE A 1021 MB HIGH CENTER IS LOCATED AT 29N92W. LATEST
AND CURRENT BUOY OBSERVATIONS ALONG WITH A RECENT ASCAT PASS SHOW
WINDS FROM THE NW-N IN DIRECTION E OF 90W WITH SPEEDS OF 15-20 KT
N OF 25N...AND SPEEDS OF 10-15 KT S OF 25N. W OF 90W...WINDS HAVE
VEERED AROUND TO THE E-SE AT 10 KT...WITH THE EXCEPTION OF THE SW
GULF WHERE WINDS ARE NE-E 10-15 KT. THE ASCAT PASS FROM 0304 UTC
LAST NIGHT REVEALED A SWATH OF NE 20 KT WINDS OVER THE FAR
EASTERN PART OF THE SW GULF. THE BUOYS ARE REPORTING SEAS IN THE
3-5 FT RANGE W OF 90W WITH LOWERS SEAS OF 1-2 FT IN THE NW
PORTION...AND SEAS OF 4-6 FT E OF 90W...WITH THE HIGHEST OF THESE
SEAS IN THE EASTERN PORTION. ALTIMETER DATA FROM LAST NIGHT SHOWED
SIMILAR VALUES.

THE AREA OF HIGH PRES WILL PREVAIL THROUGH THE FORECAST PERIOD
WHILE A WEAK COLD FRONT WILL MOVE ACROSS THE FAR NORTHERN WATERS
TUE AND WED.

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

MODEL PREFERENCE: LATEST GFS BLENDED WITH PREVIOUS OFFICIAL. FOR
WAVES USED A BLEND OF THE LATEST MWW3 AND NWPS WITH PREVIOUS FORECAST.
HIGH CONFIDENCE.

A RIDGE OF HIGH PRES PREVAILS N OF THE FORECAST AREA. LATEST
BUOY OBSERVATIONS ALONG WITH SEVERAL SHIP OBSERVATIONS SHOW
GENERALLY FRESH TO STRONG TRADES OVER THE CENTRAL CARIBBEAN
WATERS WITH SEAS IN THE 6-9 FT...EXCEPT FOR MUCH HIGHER SEAS TO
11 FT OFF THE COAST OF COLOMBIA. FRESH TRADES ARE OVER THE EASTERN
CARIBBEANSEA WITH SEAS IN THE 5-7 FT RANGE. W OF 80W...RECENT
ASCAT DATA DEPICTED MAINLY GENTLE N-NE WINDS WITH SEAS IN THE 3-5
FT RANGE EXCEPT FOR LOWER SEAS OF 2-3 FT W OF A LINE FROM EASTERN
CUBA TO HONDURAS. THE RIDGE OF HIGH PRES N OF THE AREA IS STILL
FORECAST TO RETREAT EASTWARD OVER THE NEXT COUPLE OF DAYS AS LOW
PRES AT 31N78W TRACKS SLOWLY NEWD. WITH THE RIDGE RETREATING
EASTWARD...THE PRES GRADIENT OVER THE FORECAST AREA WILL LOOSEN
ALLOWING FOR WIND SPEEDS TO DIMINISH. SEAS WILL BEGIN TO LOWER MON
THROUGH TUE...AND REMAIN AT RATHER LOW VALUES THROUGH THU.

AN ASCAT PASS FROM 0118 UTC LAST NIGHT SHOWED A LARGE SWATH OF
NE TO E 20-25 KT COVERING THE TROPICAL N ATLC WATERS S OF 18N.
BUOY REPORTS ALONG WITH AN RECENT ALTIMETER DATA SHOW SEAS MOSTLY
IN THE 8-9 FT RANGE IN NE-E SWELLS WITH A FEW SMALL POCKETS OF 10
FT SEAS. SWELLS ARE FORECAST TO GRADUALLY SUBSIDE THROUGH MON...WITH
SEAS THERE SUBSIDING TO AROUND 6 FT BY LATE MON...AND CONTINUING
WITH LITTLE CHANGE INTO THU.

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

MODEL PREFERENCE: LATEST GFS BLENDED WITH PREVIOUS OFFICIAL. FOR
WAVES USED A BLEND OF THE LATEST MWW3 AND NWPS WITH PREVIOUS
FORECAST. AVERAGE CONFIDENCE THROUGH SUN WITH STRENGTH OF WINDS
OVER FAR NW WATERS...THEN HIGH CONFIDENCE THEREAFTER.

THE LOW PRES FROM THE PREVIOUS DAYS THAT TRACKED ENE FROM THE
GULF OF MEXICO TO THE FAR NW WATERS IS PRESENTLY LOCATED AT
31N78W WITH A PRES OF 1011 MB. ITS ASSOCIATED COLD FRONT EXTENDS S
TO THE NORTHERN BAHAMAS...AND SW TO WESTERN CUBA. A SQUALL LINE
OUT AHEAD OF THE FRONT IS MARKED BY VERY ACTIVE SCATTERED TO
NUMEROUS TSTM ACTIVITY OBSERVED ON SATELLITE IMAGERY FROM N OF 26N
TO BETWEEN 73W AND 76W. RECENTLY DEVELOPED SCATTERED TSTM ACTIVITY
IS NOTED WITHIN 45 NM EITHER SIDE OF A LINE FROM 26N76W TO 24N77W.
ALL OF THIS CONVECTIVE ACTIVITY CONTAINS FREQUENT LIGHTNING
STRIKES ALONG WITH GUSTY WINDS.

LATEST SATELLITE DERIVED WINDS AND SEAS ALONG WITH SHIP...BUOY...
AND CMAN OBSERVATIONS DEPICT MODERATE TO FRESH E TO SE WINDS S OF
25N BETWEEN THE BAHAMAS AND 65W...MODERATE E-SE WINDS N OF 25N NE
AND E OF THE BAHAMAS...AND GENTLE TO MODERATE NW WINDS W OF THE
WITH THE EXCEPTION OF THE FAR NW CORNER WHERE FRESH N WINDS ARE
OBSERVED. SEAS ARE IN THE 6-8 FT RANGE S OF 25N BETWEEN 65W AND
THE BAHAMAS WITH A FEW SMALL POCKETS OF 7-9 FT SEAS BETWEEN THE SE
BAHAMAS AND HISPANIOLA. W OF THE BAHAMAS...SEAS ARE IN THE 3-5 FT
RANGE FROM 25N-27N...2-4 FT S OF 25N...AND 5-7 FT N OF 27N.

THE 1010 MB LOW PRES CENTER WILL CONTINUE TO SLOWLY MOVE NE
AWAY FROM THE AREA THROUGH SUN...THEN BEGIN TO ACCELERATE TO THE
NE SUN NIGHT AND MON PUSHING THE COLD FRONT THROUGH THE FORECAST
WATERS. THE COLD FRONT AND PRECEDING SQUALL LINE WILL SHIFT E OF
THE FORECAST WATERS TUE AS A WEAK PRES PATTERN SETS UP OVER THE
AREA. A WEAK COLD FRONT WILL BRUSH THE FAR NORTHERN WATERS WED
AND WED NIGHT...AND THE EASTERN PORTION WED NIGHT INTO THU. MOST
MODELS OVERALL SUGGEST THAT WINDS BEHIND THE FRONT WILL BE NW
GENERALLY IN THE MODERATE RANGE. WILL EVALUATE FUTURE MODEL TRENDS
WITH THIS WINDS TO SEE IF THEY TREND UPWARD AS A BROAD AREA OF
FRESH NW WINDS WILL BE PRESENT JUST TO THE N OF 31N. SEAS ARE
FORECAST TO AROUND 9 FT BEHIND THE FRONT...BUT MAY BE HIGHER
DEPENDING IF WINDS TREND UPWARD ACROSS A VERY LARGE OCEANIC FETCH
AREA.

$$

.WARNINGS...ANY CHANGES IMPACTING COASTAL NWS OFFICES WILL BE
COORDINATED THROUGH AWIPS 12 PLANET 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...
     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.HURRICANE WARNINGS.GOV/MARINE

$$

.FORECASTER AGUIRRE. NATIONAL HURRICANE CENTER.



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