000 AXNT20 KNHC 132342 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 805 PM EDT FRI JUN 13 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... A TROPICAL WAVE IS ALONG 23W/24W ACROSS THE CAPE VERDE ISLANDS S OF 17N MOVING W 10-15 KT. VERY LITTLE CONVECTION IS ASSOCIATED WITH THE WAVE. ONLY A FEW SCATTERED SHOWERS AND ISOLATED TSTMS ARE OBSERVED EMBEDDED WITHIN THE ITCZ. SURFACE DATA... SATELLITE IMAGERY AND THE SSMI-DERIVED TPW SUPPORT THE POSITION OF THE WAVE AXIS. A TROPICAL WAVE IS OVER THE ERN CARIBBEAN ALONG 64W S OF 18N MOVING W 15-20 KT. THE WAVE IS WELL DEPICTED IN THE MOISTURE PRODUCTS AND E CARIBBEAN ISLANDS SURFACE OBSERVATIONS. SCATTERED SHOWERS AND ISOLATED TSTMS ARE ACROSS THE LEEWARD ISLANDS MOST NOTABLY GUADELOUPE..ANTIGUA AND BARBUDA. THIS TROPICAL WAVE IS FORECAST BY THE COMPUTER MODELS TO MOVE OVER THE UK/US VIRGIN ISLANDS AND PUERTO RICO DURING THE NEXT 24 HOURS BRINGING INCREASED POTENTIAL FOR SHOWERS AND TSTMS. A TROPICAL WAVE EXTENDS FROM THE ERN DOMINICAN REPUBLIC TO ARUBA ALONG 70W MOVING W NEAR 10 KT. THE WAVE STILL SHOWS UP WELL ON VISIBLE SATELLITE WHERE AN INVERTED-V PATTERN IS OBSERVED IN BROAD CYCLONIC LOW-LEVEL TURNING. THIS FEATURE IS ENHANCING SOME ISOLATED SHOWER/TSTM ACTIVITY OVER HISPANIOLA WITH LITTLE IN THE WAY OF DEEP ORGANIZED CONVECTION ACROSS CARIBBEAN SEA WATERS. ...ITCZ... ITCZ AXIS IS CENTERED ALONG 8N12W 10N22W 8N27W 2N40W 2N51W. SCATTERED MODERATE CONVECTION IS FROM 4N-7N BETWEEN 30W-38W. SIMILAR CONVECTION IS ALONG THE W AFRICAN COAST FROM 4N-10N BETWEEN 1W-11W. ...DISCUSSION... GULF OF MEXICO... A MID/UPPER LEVEL CYCLONE IS CENTERED NEAR 22N94W. AS OF 2100 UTC...A WEAK SURFACE TROUGH EXTENDS ACROSS THE SW GULF FROM 23N97W TO 18N95W. A FAIR AMOUNT OF CLOUDINESS WITH EMBEDDED SHOWERS AND TSTMS IS OVER THE WESTERN HALF OF THE GULF WITH ONLY EXCEPTION ALONG THE TEXAS COASTLINE WHERE UPPER LEVEL SUBSIDENCE AND DRY AIR IS IN PLACE N OF 25N AND W OF 95W. BROAD UPPER LEVEL TROUGHING EXTENDS FROM THE W ATLC ACROSS FLORIDA AND IS AIDING IN SCATTERED SHOWERS AND TSTMS ALONG THE FLORIDA PANHANDLE AND WRN FLORIDA PENINSULA COASTLINES. A 1023 MB SURFACE HIGH OVER THE SE CONUS ENVELOPS THE ERN GULF AND THE STATE OF FLORIDA. WEAK PRESSURE GRADIENT BETWEEN THE SURFACE HIGH AND SURFACE TROUGH OVER THE SW GULF IS PRODUCING MODERATE TO OCCASIONALLY FRESH SE WINDS OVER MUCH OF THE GULF. THESE WINDS ARE EXPECTED TO PERSIST THROUGH THE WEEKEND AS HIGHER PRESSURE GRADUALLY BUILDS INTO THE CENTRAL GULF BY SUN. CARIBBEAN... A PAIR OF TROPICAL WAVES ARE MOVING WESTWARD ACROSS THE ERN CARIBBEAN. SEE TROPICAL WAVE SECTION FOR MORE DETAILS. EXPECT AN INCREASE IN WINDS AND SEAS TO ACCOMPANY THE PASSAGE OF BOTH WAVES. MODERATE TO FRESH TRADEWINDS ARE NOTED THROUGHOUT THE BASIN WITH THE STRONGEST WINDS LOCATED OFF THE COLOMBIAN COAST BETWEEN 72W-78W. IN THE UPPER LEVELS A RIDGE/TROUGH/RIDGE PATTERN DOMINATES THE BASIN. A BROAD UPPER TROUGH EXTENDING FROM AN UPPER-LEVEL LOW LOCATED NE OF THE BAHAMAS DIPS S OVER THE N CENTRAL CARIBBEAN. UPPER DIFFLUENCE BETWEEN THIS TROUGH AND AN UPPER HIGH LOCATED EAST OF THE LESSER ANTILLES IS HELPING TO INDUCE THE CONVECTIVE ACTIVITY ASSOCIATED WITH THE ABOVE MENTIONED TROPICAL WAVES. SCATTERED MODERATE CONVECTION IS OVER THE SW CARIBBEAN JUST OFFSHORE OF PANAMA AND COSTA RICA S OF 11N BETWEEN 79W-84W. THIS IS LIKELY ASSOCIATED WITH THE CLOSE PROXIMITY OF THE EPAC ITCZ AND A DIFFLUENT PATTERN ALOFT. ATLANTIC... A MID/UPPER LEVEL LOW CENTERED NEAR 28N73W IS ACROSS THE W ATLC WITH BROAD UPPER LEVEL TROUGHING EXTENDING ACROSS THE BAHAMAS INTO THE N CENTRAL CARIBBEAN. SCATTERED SHOWERS AND ISOLATED TSTMS REMAIN ACROSS THE SW BAHAMAS AND E CUBA. THE SUBTROPICAL CENTRAL ATLC IS DOMINATED BY THE SOUTHERN END OF A LONG WAVE TROUGH WHICH IS SUPPORTING A STATIONARY FRONT EXTENDING ALONG 30N34W 27N45W 28N57W. A BROKEN BAND OF LOW/MID CLOUDS WITH EMBEDDED SHOWERS IS ASSOCIATED WITH THIS FRONTAL BOUNDARY. A SECOND COLD FRONT EXTENDS NEARLY E-W ALONG 31N BETWEEN 57W-71W AND HAS A WELL DEFINED BAND OF CLOUDS. THE UPPER LEVELS OF THE SUBTROPICAL ERN ATLC IS DOMINATED BY A RIDGE. IN THE TROPICS... AN UPPER LEVEL HIGH IS CENTERED NEAR 14N45W WITH THE ANTICYCLONIC FLOW REACHING THE SE CARIBBEAN TO THE WEST AND THE CAPE VERDE ISLANDS TO THE EAST. UPPER DIFFLUENCE ASSOCIATED WITH THIS SYSTEM IS ENHANCING CONVECTION ALONG THE ITCZ. $$ HUFFMAN