000 AXNT20 KNHC 262327 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 805 PM EDT SAT JUL 26 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 25W/26W S OF 20N MOVING W NEAR 15 KT. WELL DEFINED LOW LEVEL INVERTED-V CURVATURE IS OBSERVED ON SATELLITE IMAGERY WITH NO SHOWERS/CONVECTION. TROPICAL WAVE IS ALONG 47W/48W S OF 24N MOVING W 10-15 KT WITH A WEAK 1012 MB LOW ALONG THE WAVE NEAR 19N. WELL DEFINED LOW LEVEL SWIRL ASSOCIATED WITH THE SURFACE LOW WITH THE ASSOCIATED CONVECTION DISPLACED TO THE NE OF THE WAVE AXIS. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS FROM 21N-24N BETWEEN 43W-46W. TROPICAL WAVE IS ALONG 75W S OF 18N MOVING W NEAR 20 KT. WEAK INVERTED-V CURVATURE IS OBSERVED ON VISIBLE SATELLITE IMAGERY. WAVE IS EMBEDDED WITHIN DRY STABLE AIR OVER THE CENTRAL CARIBBEAN...THUS NO ASSOCIATED SHOWERS/CONVECTION. TROPICAL WAVE THAT WAS ALONG 94W IS NO LONGER IN THE ATLC BASIN. ...THE ITCZ... ITCZ AXIS IS CENTERED ALONG 14N16W 7N38W 12N47W 9N55W 10N63W. ISOLATED CLUSTERS OF SCATTERED MODERATE CONVECTION ARE FROM 2N-9N BETWEEN 32W-39W. ...DISCUSSION... GULF OF MEXICO... BROAD UPPER RIDGE ANCHORED OVER CENTRAL TEXAS EXTENDS AN AXIS E ACROSS THE SE U.S. INTO THE W ATLC NEAR THE GEORGIA/SOUTH CAROLINA BORDER COVERING THE N GULF. AFTERNOON THUNDERSTORMS GENERATED FROM OVER GEORGIA TO MISSISSIPPI ARE MOVING INTO THE GULF WATERS FROM THE FLORIDA THE FLORIDA PANHANDLE NEAR THE BIG BEND AREA TO NEAR NEW ORLEANS LOUISIANA. AN UPPER TROUGH COVERS THE SW GULF FROM THE YUCATAN PENINSULA TO INLAND OVER MEXICO WITH AN UPPER TROUGH OVER THE W ATLC COVERING THE FLORIDA STRAITS. AFTERNOON THUNDERSTORMS HAVE DEVELOPED OVER THE FLORIDA PENINSULA AND CUBA BUT ARE NOT MOVING INTO THE GULF WATERS. A WEAK SURFACE RIDGE REMAINS IN CONTROL OF THE GULF ANCHORED BY A 1021 MB HIGH NEAR 27N93W THUS GIVING THE GULF LIGHT WINDS. CARIBBEAN SEA... AN UPPER RIDGE COVERS THE W CARIBBEAN EXTENDING FROM COLOMBIA NW TO JUST S OF THE YUCATAN CHANNEL GIVING THE SW CARIBBEAN SCATTERED SHOWERS/ISOLATED THUNDERSTORMS INLAND AND ALONG THE COASTAL WATERS OF PANAMA. AFTERNOON THUNDERSTORMS HAVE DEVELOPED INLAND OVER CUBA...HISPANIOLA...AND JAMAICA MOVING S INTO THE IMMEDIATE COASTAL WATERS. OTHERWISE THE CARIBBEAN IS DOMINATED BY STRONG SUBSIDENCE AND RATHER DRY AIR. A TIGHT PRESSURE GRADIENT BETWEEN THE SURFACE RIDGE DOMINATING THE ATLC AND THE LOWER PRESSURE OVER SOUTH AMERICA IS GENERATING MODERATE/STRONG EASTERLY TRADE WINDS ACROSS THE AREA WITH THE STRONGEST WINDS ALONG THE COAST OF COLOMBIA. A SMALL UPPER LOW IS IN THE SE CARIBBEAN JUST W OF THE WINDWARD ISLANDS NEAR 12N62W GENERATING ISOLATED SHOWERS S OF 13N BETWEEN 60W-65W INCLUDING TRINIDAD AND TOBAGO. ATLANTIC OCEAN... THE UPPER RIDGE DOMINATING THE N GULF OF MEXICO EXTENDS INTO THE W ATLC NEAR THE GEORGIA/SOUTH CAROLINA BORDER TO NEAR 77W. A BROAD UPPER TROUGH COVERS THE REMAINDER OF THE W ATLC INTO THE CENTRAL ATLC INCLUDING THE FLORIDA STRAITS WITH AN EMBEDDED UPPER LOW NEAR 26N63W. THIS IS GENERATING SCATTERED SHOWERS/ ISOLATED THUNDERSTORMS FROM 21N-32N BETWEEN 62W-78W INCLUDING PORTIONS OF THE BAHAMA ISLANDS. A BROAD UPPER RIDGE DOMINATES THE REMAINDER OF THE ATLC EXTENDING FROM AN UPPER HIGH ALONG THE W COAST OF AFRICA NEAR THE BORDER OF MOROCCO AND WESTERN SAHARA TO 45W. A 1026 MB HIGH IS OVER THE W ATLANTIC NEAR 36N56W. ANOTHER 1023 MB HIGH IS OVER THE E ATLANTIC N OF THE CANARY ISLANDS NEAR 32N18W. BOTH HIGHS ARE PRODUCING FAIR WEATHER. AN AREA OF DUST HAS MOVED OFF W AFRICA IS NOW FROM 5N-25N E OF 40W MOVING W. IN THE UPPER LEVELS...AN UPPER LEVEL LOW IS CENTERED OVER THE W ATLANTIC NEAR 28N62W. A VERY LARGE UPPER LEVEL HIGH IS CENTERED OVER W AFRICA NEAR 22N12W. A RIDGE AXIS EXTENDS W FROM THE HIGH TO 22N45W. ANTICYCLONIC FLOW IS E OF 45W. EXPECT THE CONVECTION OVER THE CENTRAL ATLANTIC E OF THE TROPICAL WAVE TO ADVECT TOWARDS THE NW DURING THE NEXT 24 HOURS. A BROAD SURFACE RIDGE DOMINATES THE ATLC WITH A 1022 MB HIGH JUST W OF THE MADEIRA ISLANDS AND A 1027 MB HIGH IN THE FAR N/CENTRAL ATLC. $$ WALLACE