000 AXNT20 KNHC 062350 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 805 PM EDT THU AUG 06 2009 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 32W S OF 17N MOVING W NEAR 13 KT. THIS WAVE COINCIDES WITH A DEEP LAYER MOISTURE MAXIMUM OBSERVED IN TOTAL PRECIPITABLE WATER IMAGERY. ISOLATED MODERATE CONVECTION IS FROM 13N-15N BETWEEN 30W-34W. A TROPICAL WAVE IS ALONG 49W S OF 14N MOVING W NEAR 18 KT. THIS WAVE REMAINS ON THE LEADING EDGE OF DRY SAHARAN AIR AND DUST INHIBITING DEEP CONVECTION ALONG THE WAVE AXIS. HOWEVER... SCATTERED SHOWERS ARE FROM 10N-12N BETWEEN 46W-50W. A TROPICAL WAVE IS ALONG 66W S OF 18N MOVING W NEAR 15 KT. THIS WAVE COINCIDES WITH A DEEP LAYER MOISTURE MAXIMUM THAT STRETCHES NWD INTO THE SW NORTH ATLC DUE TO AN UPPER LEVEL LOW CENTERED NEAR 23N67W. INTERACTIONS BETWEEN THE TROPICAL WAVE AND UPPER LEVEL LOW ARE PRODUCING SCATTERED SHOWERS AND ISOLATED MODERATE CONVECTION FROM 10N-19N BETWEEN 60W-70W. A TROPICAL WAVE IS ALONG 82W S OF 21N MOVING W NEAR 15 KT. THIS WAVE LIES IN A BROAD AREA OF DEEP LAYER MOISTURE OBSERVED IN TOTAL PRECIPITABLE WATER IMAGERY. THIS WAVE CONTINUES MOVING BENEATH A DIFFLUENT PATTERN ALOFT ENHANCING SCATTERED MODERATE CONVECTION OVER THE SW CARIBBEAN S OF 12N AND ACROSS PANAMA AND COSTA RICA. ALSO SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS OVER THE NW CARIBBEAN N OF 18N BETWEEN 80W-89W...INCLUDING PORTIONS OF WRN CUBA AND THE YUCATAN PENINSULA. ...ITCZ... THE ITCZ AXIS IS CENTERED ALONG 11N16W 11N21W 13N31W 13N34W 12N40W 10N43W 8N48W 7N50W AND INTO NRN SOUTH AMERICA NEAR 6N55W. CLUSTERS OF SCATTERED MODERATE/ISOLATED STRONG CONVECTION ARE FROM 9N-15N BETWEEN 13W-24W. SCATTERED MODERATE CONVECTION IS FOCUSED ALONG A SURFACE TROUGH EMBEDDED WITHIN THE ITCZ THAT EXTENDS FROM 16N39W TO 9N42W. THIS CONVECTION IS LOCATED FROM 11N-15N BETWEEN 39W-45W. ...DISCUSSION... GULF OF MEXICO... AN UPPER LEVEL TROUGH IS ACROSS THE SE CONUS AND EXTENDS SW INTO THE GULF OF MEXICO TO AN UPPER LOW CENTERED NEAR 23N91W. THIS UPPER LEVEL FEATURE IS SUPPORTING A WEAK SURFACE TROUGH THAT EXTENDS FROM SE GEORGIA INTO THE NE GULF ALONG 30N84W 26N90W TO 26N93W. WEAK LOW-LEVEL CONVERGENCE OF PRIMARILY NE WINDS ACROSS MUCH OF THE GULF ARE GENERATING SCATTERED SHOWERS AND ISOLATED TSTMS OVER A BULK OF THE GULF WATERS. LIGHTNING DATA PLACES MOST OF THIS ACTIVITY FROM 24N-28N BETWEEN 84W-94W. ALSO... ATMOSPHERIC INSTABILITY SE OF THE SURFACE TROUGH IS GENERATING SCATTERED SHOWERS AND TSTMS ACROSS INTERIOR PORTIONS OF THE FLORIDA PENINSULA N OF 27N. WITH THE UPPER LEVEL LOW CENTERED OVER THE S/CENTRAL GULF...UPPER LEVEL DIFFLUENCE ALONG WITH THE PRESENCE OF THE TROPICAL WAVE ALONG 82W IN THE NW CARIBBEAN IS GENERATING SCATTERED SHOWERS AND TSTMS OVER WRN CUBA...THE STRAITS OF FLORIDA...YUCATAN PENINSULA AND NEARBY COASTAL WATERS. CARIBBEAN SEA... TWO TROPICAL WAVES ARE TRACKING WWD ACROSS THE CARIBBEAN BASIN. ONE IS LOCATED ALONG 82W WITH AN UPPER LEVEL DIFFLUENT PATTERN PRESENT OVER THE WRN CARIBBEAN. SCATTERED SHOWERS AND TSTMS ARE S OF 16N AND W OF A LINE FROM 16N82W TO 11N74W OVER NRN COLOMBIA. HEAVY RAINFALL AND POSSIBLE FLOODING IS EXPECTED OVER INTERIOR PORTIONS OF COSTA RICA...NICARAGUA...AND HONDURAS DURING THE NEXT 24-36 HOURS AS THE WAVE CONTINUES WWD. THE NRN PORTION OF THE TROPICAL WAVE IS GENERATING SCATTERED SHOWERS AND TSTMS N OF 18N BETWEEN 80W-89W...AS UPPER LEVEL DIFFLUENCE E OF AN UPPER LOW OVER THE SW GULF OF MEXICO IS HELPING TO SUPPORT THE CONVECTION OVER THE NW CARIBBEAN...CUBA AND THE YUCATAN PENINSULA. THE OTHER TROPICAL WAVE IS ALONG 66W AND IS IMPACTING THE ERN CARIBBEAN WITH SCATTERED SHOWERS AND ISOLATED TSTMS E OF 70W. IN BETWEEN THESE TWO TROPICAL WAVES MIDDLE TO UPPER LEVEL DRY AIR IN SUBSIDENCE PREVAILS AS UPPER TROUGHING EXTENDS FROM AN UPPER LEVEL LOW LOCATED N OF PUERTO RICO NEAR 23N67W TO THE DE LA GUAJIRA PENINSULA IN NRN COLOMBIA. FRESH TO STRONG TRADE WINDS ARE ACROSS THE CARIBBEAN WITH THE HIGHEST WINDS NEAR THE COAST OF COLOMBIA. ATLANTIC OCEAN... UPPER LEVEL DIFFLUENCE ASSOCIATED WITH AN UPPER LEVEL ANTICYCLONE CENTERED OVER THE NW BAHAMAS NEAR 25N77W IS SUPPORTING SCATTERED SHOWERS AND TSTMS OVER NRN FLORIDA N OF 27N AND THE ADJACENT COASTAL WATERS ALONG THE NERN FLORIDA COAST. ISOLATED SHOWERS EXTEND NE WITHIN 90 NM EITHER SIDE OF A LINE FROM 29N78W TO BEYOND 32N73W. FARTHER TO THE E...AN UPPER LEVEL LOW IS CENTERED NEAR 23N67W. A SURFACE TROUGH IS ANALYZED IN THE VICINITY OF THIS UPPER LOW AND EXTENDS FROM 30N66W TO 23N69W. SCATTERED SHOWERS COVER THE AREA FROM 18N-32N BETWEEN 63W-72W. ELSEWHERE ACROSS THE CENTRAL AND ERN ATLC...A BROAD SURFACE RIDGE REMAINS IN CONTROL ANCHORED BY A 1027 MB SURFACE HIGH CENTERED NEAR 33N50W BRINGING GENERALLY FAIR WEATHER ACROSS THE REMAINDER OF THE BASIN E OF 62W. THE REMAINDER OF THE TROPICAL ATLC IS UNDER A BROAD UPPER LEVEL RIDGE WITH AXIS ALONG 14N THAT IS ENHANCING CONVECTION ALONG THE ITCZ AND SURFACE TROUGH NEAR 41W. $$ HUFFMAN