000
AGXX40 KNHC 110658
MIMATS

MARINE WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
300 AM EDT TUE AUG 11 2009

MARINE WEATHER DISCUSSION FOR THE GULF OF MEXICO...CARIBBEAN SEA
AND SOUTHWEST NORTH ATLC S OF 31N W OF 55W.

GULF OF MEXICO...A WEAK RIDGE...WITH VARIABLE WINDS AT 5 TO 10 
KT AND SEAS 1 TO 3 FT...WILL LINGER ACROSS THE NORTHERN GULF 
WATERS UNTIL WED WHEN IT IS NUDGED SOUTHWARD BY A COLD FRONT 
PUSHING S TROUGH THE MISSISSIPPI VALLEY. THE MORE AMPLIFIED 
PATTERN ASSOCIATED WITH THE FRONT WILL EAT INTO THE DEEP LAYERED 
RIDGING IN PLACE OVER THE GULF...WITH THE SURFACE RIDGE 
REBUILDING OVER THE GULF ON FRI/SAT.  GENERALLY E TO SE WINDS AT 
10 TO 15 KT ARE EXPECTED WELL S OF THE RIDGE EXCEPT FOR THE LATE 
AFTERNOON AND EARLY EVENING BACKING OF WINDS TO NE AT 15 TO 20 
KT ALONG THE NE COAST YUCATAN PENINSULA.

CARIBBEAN AND TROPICAL ATLC...STRONG ELY TRADES OVER THE CENTRAL 
CARIBBEAN IN THE 20 TO 25 KT RANGE...INCLUDING THE WINDWARD 
PASSAGE. GRADIENT SHOULD RELAX AND DROP TODAY THROUGH FRIDAY. 
WITH WINDS HIGHEST...20 TO 25 KT...NEAR THE COAST OF COLOMBIA. A 
TROPICAL WAVE ALONG 74W HAS VERY LITTLE CONVECTION. A WAVE ALONG 
60W MOVING W NEAR 10 KT HAS CONVECTION RE-BUILDING NEAR ITS AXIS 
FROM 12N TO 14N. ANOTHER WAVE ALONG 50W IS KICKING OFF 
CONVECTION ALONG ASSOCIATED WITH ITS RELATIVELY STRONG NORTHERN 
VORT CENTER WHICH IS EXPECTED TO MOVE ON A MORE NW PATH INTO THE 
GREATER ANTILLES THU-SAT. THIS WAVE WILL MOVE W AT 15 KT INTO E 
CARIBBEAN BY THU...WITH THE NORTHERN VORT CENTER AND ASSOCIATED 
SURFACE TROUGH POSSIBLY BREAKING AWAY FROM THE WAVE LATE IN THE 
WEEK. A THIRD WAVE IS ALONG 27W WITH A SURFACE LOW INDICATED 
NEAR 14N27W AT 00Z. THE 2240 UTC ASCAT PASS SUPPORTED THIS 
SURFACE LOW. PREVIOUS GUIDANCE APPEARS TO HAVE MOVED IT WESTWARD 
TOO QUICKLY AND CURRENT NHC THINKING IS MUCH SLOWER AND STILL 
JUST E OF THE TROPICAL ATLC ZONE EARLY NEXT WEEK. SYSTEM IS 
NOTED IN THE HIGH SEAS FORECAST...WITH MENTION OF POSSIBLE 
TROPICAL CYCLONE PER NHC. 

SW N ATLC...A WEAKENING SURFACE TROUGH FROM 31N55W TO 26N74W 
SHOULD WASH OUT TUE. SHOWER ACTIVITY ALONG THE TROUGH HAS 
DISSIPATED TONIGHT. AN ATLC E TO W RIDGE IS BUILDING OVER 
NORTHERN WATERS N OF THE DISSIPATING TROUGH WILL MEANDER OVER 
THE SW N ATLC ZONE THROUGH THE REMAINDER OF PERIOD. THE NORTHERN 
EXTENSION OF A TROPICAL WAVE WILL PASS THROUGH THE WATERS S OF 
24N THU AND FRI WITH AN INCREASE IN WIND AND SEAS. THE MODELS 
GENERALLY AGREE ON CARRYING AT LEAST A PORTION OF THE VORTICITY 
ASSOCIATED WITH THE WAVE NORTHWESTWARD TOWARD THE WEAKNESS IN 
THE DEEP LAYER RIDGE OVER THE EASTERN GULF OF MEXICO. AS A 
RESULT...STRONG SOUTHEASTERLY FLOW WILL CONTINUE W OF THE 
BAHAMAS ON SAT AS THE SURFACE TROUGHING SLOWLY LIFTS NW THROUGH 
S FLORIDA AND THE RIDGE BUILDS TO ITS NORTH.

 
WARNINGS

ATLC...
.NONE. 

CARIBBEAN...
.NONE. 

GULF OF MEXICO...
.NONE.

$$
FORECASTER SCHAUER CLARK/NELSON