000 AXNT20 KNHC 272342 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 805 PM EDT SUN JUL 27 2008 TROPICAL WEATHER DISCUSSION FOR NORTH AMERICA...CENTRAL AMERICA...GULF OF MEXICO...CARIBBEAN SEA...NORTHERN SECTIONS OF SOUTH AMERICA...AND ATLANTIC OCEAN TO THE AFRICAN COAST FROM THE EQUATOR TO 32N. THE FOLLOWING INFORMATION IS BASED ON SATELLITE IMAGERY...METEOROLOGICAL ANALYSIS...WEATHER OBSERVATIONS...AND RADAR. BASED ON 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 2315 UTC. ...TROPICAL WAVES... TROPICAL WAVE IS ALONG 34W S OF 20N MOVING W NEAR 20 KT. WELL DEFINED LOW LEVEL INVERTED-V CURVATURE IS OBSERVED ON SATELLITE IMAGERY WITH ISOLATED SHOWERS EMBEDDED WITHIN 90/120 OF THE ITCZ. TROPICAL WAVE IS ALONG 52W/53W S OF 24N MOVING W 10-15 KT. WELL DEFINED LOW LEVEL INVERTED-V CURVATURE IS OBSERVED ON SATELLITE IMAGERY. WAVE IS EMBEDDED WITHIN DRY STABLE AIR OVER THE CENTRAL ATLC...THUS NO ASSOCIATED SHOWERS/CONVECTION. TROPICAL WAVE IS ALONG 81W S OF 20N MOVING W NEAR 15 KT. WEAK INVERTED-V CURVATURE IS OBSERVED ON VISIBLE SATELLITE IMAGERY. WAVE IS EMBEDDED WITHIN SOME RATHER DRY STABLE AIR OVER THE W CARIBBEAN...THUS NO ASSOCIATED SHOWERS/CONVECTION. ...THE ITCZ... ITCZ AXIS IS CENTERED ALONG 13N16W 14N24W 4N45W 10N59W. SCATTERED/NUMEROUS STRONG CONVECTION HAS MOVED OFF W AFRICA FROM 10N-13N E OF 18W TO INLAND OVER S SENEGAL/GUINEA-BISSAU. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS WITHIN 90 NM OF LINE FROM 7N14W TO 11N19W AND WITHIN 90 NM N OF THE ITCZ FROM 43W-46W. ...DISCUSSION... GULF OF MEXICO... BROAD UPPER RIDGE ANCHORED OVER THE DESERT SW EXTENDS AN AXIS E ACROSS THE TEXAS AND THE N GULF COAST INTO THE W ATLC COVERING MOST OF THE GULF EXCEPT THE SW GULF WHERE AN UPPER TROUGH COVERS THE BAY OF CAMPECHE INTO S MEXICO NEAR TUXPAN. AN UPPER LOW OVER CENTRAL CUBA COVERS THE FAR SE GULF AND THE FLORIDA STRAITS. HEAVY SHOWERS/SCATTERED THUNDERSTORMS HAVE DEVELOPED OVER THE LOWER MISSISSIPPI VALLEY TO OVER SE LOUISIANA JUST MOVING INTO THE GULF WATERS. REMNANT SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS DOT THE NE GULF N OF 24N E OF 92W WITH AFTERNOON THUNDERSTORMS CONTINUING OVER ALL OF FLORIDA JUST INTO THE GULF WATERS. A WEAK SURFACE RIDGE REMAINS IN CONTROL OF THE GULF ANCHORED BY A 1017 MB HIGH NEAR 25N91W THUS GIVING THE GULF LIGHT WINDS. CARIBBEAN SEA... AN UPPER LOW IS OVER CENTRAL CUBA NEAR CAMAGUEY COVERING THE N CARIBBEAN N OF 16N FROM HISPANIOLA TO W CUBA INCLUDING JAMAICA AND THE CAYMAN ISLANDS. THIS IS ENHANCING THE AFTERNOON THUNDERSTORMS THAT HAVE DEVELOPED N OF 17N INCLUDING CUBA... HISPANIOLA...CAYMAN ISLANDS...AND JAMAICA. AN UPPER RIDGE COVERS THE SW CARIBBEAN EXTENDING FROM COLOMBIA TO ACROSS NICARAGUA GENERATING SCATTERED SHOWERS/ISOLATED THUNDERSTORMS S OF 12N FROM COLOMBIA TO S NICARAGUA INCLUDING PANAMA AND COSTA RICA. OTHERWISE THE CARIBBEAN IS DOMINATED BY STRONG SUBSIDENCE AND RATHER DRY AIR. THE TIGHT PRESSURE GRADIENT BETWEEN THE RATHER STRONG SURFACE RIDGE DOMINATING THE ATLC AND THE LOWER PRESSURE OVER SOUTH AMERICA CONTINUES TO GENERATE MODERATE/STRONG EASTERLY TRADE WINDS ACROSS THE AREA WITH THE STRONGEST WINDS ALONG THE COAST OF COLOMBIA. A WEAK UPPER LOW REMAINS IN THE SE CARIBBEAN JUST W OF THE WINDWARD ISLANDS NEAR 13N63W GENERATING ISOLATED SHOWERS MAINLY S OF 11N E OF 64W INTO THE W TROPICAL ATLC INCLUDING TRINIDAD AND TOBAGO. ATLANTIC OCEAN... THE UPPER RIDGE DOMINATING THE GULF OF MEXICO EXTENDS INTO THE W ATLC NEAR THE GEORGIA/SOUTH CAROLINA BORDER TO NEAR 74W. A BROAD UPPER TROUGH COVERS THE REMAINDER OF THE W ATLC EXTENDING FROM AN UPPER LOW NEAR 30N61W TO A SECOND UPPER LOW NEAR 23N69W TO YET A THIRD UPPER LOW OVER CENTRAL CUBA NEAR CAMAGUEY AND INTO THE N CARIBBEAN. THIS UPPER TROUGH IS GENERATING A BROAD AREA OF SCATTERED SHOWERS/ISOLATED THUNDERSTORMS FROM 22N-32N W OF 63W TO OVER FLORIDA AND INTO THE FLORIDA STRAITS. A SURFACE TROUGH IS IN THE CENTRAL ATLC...PREVIOUSLY A PORTION OF A TROPICAL WAVE... EXTENDING FROM 32N45W TO 26N50W GENERATING SCATTERED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS WITHIN 120/150 NM SE OF THE WAVE AXIS. A BROAD UPPER RIDGE DOMINATES THE REMAINDER OF THE ATLC ANCHORED BY AN UPPER HIGH NEAR 20N28W. THE ATLC IS ALSO DOMINATED BY A STRONG SURFACE RIDGE ANCHORED WELL N OF THE REGION WITH A WEAKNESS IN THE VICINITY OF THE SURFACE TROUGH. THIS IS GIVING THE REMAINDER OF THE ATLC FAIR WEATHER THIS EVENING. $$ WALLACE