000
AGXX40 KNHC 131757
MIMATS

MARINE WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
205 PM EDT MON AUG 13 2007

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

GULF OF MEXICO...WEAK TROUGH FROM 30N91W TO 25N94W DRIFT W AS UPPER 
LEVEL CYCLONE DOES.  VORTICITY MAXIMA ATOP TROPICAL WAVE CREST ALONG 
87W DEFINED AS LOW PRES CENTER 1011 MB AT 22N87W ENTER GULF OF 
MEXICO THROUGH YUCATAN PASSAGE IS EXPECTED TO DEVELOP MORE 
CONVECTION IN INTENSITY AND COVERAGE UNDER DIFFLUENT FLOW ALOFT. 
ATLC RIDGE THAT EXTENDED INTO NERN GULF OF MEXICO RETREATS E OF 
FLORIDA AND WAITS FOR TROUGH...WAVE AND UPPER LEVEL CYCLONE TO DRIFT 
W OVER TEXAS BEFORE REBUILDING BACK INTO GULF FRI. 
      
TROPICAL ATLC AND CARIBBEAN...TRPCL WAVE ALONG 87W MOVES W OF BASIN 
TONIGHT DRAGGING MOST OF ITS SCATTERED TO NUMEROUS CONVECTION ALONG 
WITH IT.  TROPICAL WAVE WELL E OF 55W HAS FORMED LOW PRES 1005 MB 
...NOW TROPICAL DEPRESSION FOUR...MOVING W AT 15 KT.  AGGRESSIVE GFS 
BRINGS IT INTO TRPCL ATLC AS HURRICANE WHILE OTHER MODELS ARE MORE 
MODERATE ABOUT IT.  CIRCULATION AND CONVECTION HAVE SURVIVED A VERY 
HOSTILE UPPER LEVEL ENVIRON AS IT APPROACHES 55W WHERE SHEAR 
DIMINISHES WHILE SST REMAIN VERY WARM.     

SW N ATLC...WEAK FRONTAL TROUGH OVER NRN PORTIONS OF SW N ATLC 
WATERS MOVE SE REACHING FROM BERMUDA TO NW BAHAMAS EARLY TUE AND 
STALL FROM BERMUDA TO CENTRAL BAHAMAS LATE WED...THEN GRADUALLY 
DISSIPATE THU AND FRI.  ATLC RIDGE REBUILDS W WED AND THU.  BY 
FRI...ATLC RIDGE BUILDS FROM BERMUDA ACROSS NE FL INTO GULF. EXTREME 
SE PART OF BASIN MIGHT BE SUBJECT ON FRI AND SAT TO EFFECTS OF NOW 
TROPICAL DEPRESSION FOUR...POSSIBLE HURRICANE BY THEN.

WARNINGS...
ATLANTIC...
NONE.

CARIBBEAN...
HURRICANE CONDITIONS EXPECTED THU AND FRI N OF 14N E OF 67W...AMZ087 

GULF OF MEXICO...
NONE.

FORECASTER WALLY BARNES