000 AXNT20 KNHC 210005 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 805 PM EDT SUN AUG 20 2006 TROPICAL WEATHER DISCUSSION FOR NORTH AMERICA...CENTRAL AMERICA...THE GULF OF MEXICO...THE CARIBBEAN SEA...NORTHEASTERN SECTIONS OF SOUTH AMERICA...AND THE ATLANTIC OCEAN TO THE AFRICAN COAST FROM THE EQUATOR TO 32N. THE FOLLOWING INFORMATION IS BASED ON SATELLITE IMAGERY...WEATHER OBSERVATIONS...RADAR... AND METEOROLOGICAL ANALYSIS. BASED ON 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 2315 UTC. ...TROPICAL WAVES... AN ATLANTIC OCEAN TROPICAL WAVE IS ALONG 33W/34W SOUTH OF 20N MOVING WEST 20 KT. THIS WAVE IS NOT GENERATING ANY DEEP CONVECTIVE PRECIPITATION ALONG IT AT THIS MOMENT. PRECIPITATION IS IN THE ITCZ FROM 6N TO 10N BETWEEN 30W AND 42W. LOW CLOUDS AND POSSIBLE SHOWERS ARE WITHIN 60 TO 90 NM ON EITHER SIDE OF A LINE THAT CURVES FROM 14N44W TO 17N42W 19N40W 19N36W. AN ATLANTIC OCEAN TROPICAL WAVE IS ALONG 47W/48W SOUTH OF 20N MOVING WEST 15 TO 20 KT. SAHARAN DUST WAS SEEN EAST OF THIS WAVE IN EARLIER VISIBLE IMAGERY. NO DEEP CONVECTIVE PRECIPITATION. A CARIBBEAN SEA TROPICAL WAVE IS PASSING PUERTO RICO ALONG 67W/68W SOUTH OF 18N MOVING WEST 10 TO 15 KT. THIS WAVE ALL BY ITSELF REALLY DOES NOT APPEAR TO BE CAUSING ANY DEEP CONVECTIVE PRECIPITATION. ONE CELL OF STRONG SHOWERS/THUNDERSTORMS IS IN THE WATERS JUST WEST OF PUERTO RICO RIGHT NOW. A TROPICAL WAVE WAS ADDED TO THE 20/1800 UTC SURFACE MAP ANALYSIS BASED ON HOVMOLLER DIAGRAMS/SATELLITE IMAGERY. IT IS IN THE WESTERN CARIBBEAN SEA ALONG 81W/82W SOUTH OF 19N MOVING WEST 10 TO 15 KT. IT IS MOVING THROUGH THE AREA OF THE WESTERN CARIBBEAN SEA WITH A MIXTURE OF FEATURES IN IT. ...THE ITCZ... ITCZ 11N14W 9N23W 9N32W 9N35W 8N42W 9N47W 8N50W 7N59W. NUMEROUS STRONG SHOWERS AND THUNDERSTORMS ARE OCCURRING FROM 12N TO 14N BETWEEN 14W AND 18W...FROM 11N TO 12N BETWEEN 17W AND 19W...AND FROM 9N TO 10N BETWEEN 16W AND 18W. ALL THIS CONVECTIVE PRECIPITATION EASILY ACCOMPANIES THE NEXT TROPICAL WAVE THAT WILL HIT THE ATLANTIC OCEAN. SCATTERED MODERATE SHOWERS TO ISOLATED STRONG THUNDERSTORMS ARE FOUND FROM 6N TO 10N BETWEEN 30W AND 48W. ISOLATED MODERATE SHOWERS ARE FOUND ELSEWHERE FROM 6N TO 8N BETWEEN 20W AND 26W...AND FROM 6N TO 12N BETWEEN 48W AND 60W. ...DISCUSSION... THE GULF OF MEXICO...THE ATLANTIC OCEAN WEST OF 70W... AND THE NORTHWESTERN CARIBBEAN SEA NORTHWEST OF 20N78W 16N85W... MIDDLE TO UPPER LEVEL LOW PRESSURE CENTERS ABOUND. THE FIRST LOW CENTER IS IN THE WESTERN ATLANTIC OCEAN NEAR 28N79W. SCATTERED MODERATE TO ISOLATED STRONG SHOWERS AND THUNDERSTORMS COVER THE BAHAMAS AND THE ATLANTIC WATERS NORTH OF THE BAHAMAS FROM 24N TO 29N BETWEEN 76W AND 80W. SHOWERS AND THUNDERSTORMS ARE SPREAD OVER FLORIDA FROM SOUTH FLORIDA TO SOUTH OF TAMPA TO NORTH CENTRAL FLORIDA. A MIDDLE TO UPPER LEVEL LOW IN THE SOUTHWESTERN CORNER OF THE AREA IS THE SECOND MOST WELL-DEFINED LOW IN THE AREA. UPPER LEVEL ANTICYCLONIC FLOW FROM A RIDGE PASSES FROM THE SOUTHEASTERN U.S.A. TO TEXAS AND NORTHERN MEXICO NORTHWARD THROUGH ARIZONA AND NEW MEXICO. SHOWERS AND THUNDERSTORMS HAVE DEVELOPED ALONG THE WESTERN COAST OF MEXICO IN UPPER LEVEL DIFFLUENT FLOW BETWEEN THE RIDGE AND THE SOUTHWESTERN GULF OF MEXICO LOW CENTER. SCATTERED STRONG SHOWERS AND THUNDERSTORMS STRETCH FROM NORTHERN GUATEMALA TO THE NORTHERN YUCATAN PENINSULA. SCATTERED MODERATE SHOWERS TO ISOLATED STRONG THUNDERSTORMS ARE IN THE ISTHMUS OF TEHUANTEPEC ON THE SOUTHERN SIDE OF THE LOW CENTER. SCATTERED MODERATE SHOWERS TO ISOLATED STRONG THUNDERSTORMS ARE IN THE CENTRAL GULF OF MEXICO FROM 23N TO 27N BETWEEN 86W AND 92W... WITH A NOT-SO-WELL-DEFINED MIDDLE TO UPPER LEVEL LOW PRESSURE CENTER. WIDELY SCATTERED MODERATE SHOWERS TO ISOLATED STRONG THUNDERSTORMS ARE NORTH OF 20N BETWEEN 80W AND WESTERN CUBA. OTHER STRONG SHOWERS AND THUNDERSTORMS ARE IN CUBA AND ADJACENT WATERS FROM 21N TO 22N BETWEEN 75W AND 78W. A SURFACE TROUGH IS IN THE WATERS OF THE NORTHEASTERN CORNER OF THE GULF... FROM A 1015 MB LOW PRESSURE CENTER IN SOUTHEASTERN GEORGIA. THIS LOW CENTER HAD BEEN IN THE ATLANTIC WATERS 24 HOURS AGO. THE REST OF THE CARIBBEAN SEA... THE WEST CENTRAL CARIBBEAN SEA IS MIXTURE OF AT LEAST A FEW FEATURES COMING TOGETHER AT THE SAME TIME. REMNANTS OF A MIDDLE TO UPPER LEVEL LOW CENTER IN THE NORTHWESTERN CORNER OF THE AREA FROM 24 HOURS AGO STILL ARE PRESENT. ADD TO THAT SOME MIDDLE TO UPPER LEVEL FLOW WHICH PASSES OVER THE ISTHMUS OF TEHUANTEPEC TO THE SOUTH OF A SOUTHWESTERN GULF OF MEXICO LOW CENTER...REACHES THE YUCATAN PENINSULA...AND CURVES SOUTHWARD OVER NICARAGUA TOWARD COSTA RICA. ADD TO THAT AN UPPER LEVEL RIDGE ALONG 78W/79W. NUMEROUS STRONG SHOWERS AND THUNDERSTORMS WERE EVIDENT AT 20/1845 UTC FROM 13N TO 15N BETWEEN 77W AND 80W. THE CLOUD TOP TEMPERATURES HAVE WARMED IN MUCH OF THAT AREA SINCE THAT TIME. THE COLDEST CLOUD TOP TEMPERATURES AND STRONG THUNDERSTORMS ARE FOUND NOW FROM 15N TO 17N BETWEEN 78W AND 79W. OTHER ISOLATED MODERATE SHOWERS AND THUNDERSTORMS ARE FOUND FROM 16N TO 20N BETWEEN 74W AND 80W. THE NORTHEASTERN CORNER OF THE AREA STILL IS UNDER THE INFLUENCE OF A MIDDLE TO UPPER LEVEL TROUGH THAT ORIGINATES IN THE ATLANTIC OCEAN...THROUGH 26N62W TO 22N64W TO 20N66W. MIDDLE TO MOSTLY UPPER LEVEL EASTERLY FLOW MOVES INTO THE REST OF THE CARIBBEAN SEA FROM THE ATLANTIC OCEAN. THE ATLANTIC OCEAN... A MIDDLE TO UPPER LEVEL TROUGH PASSES THROUGH 32N60W TO 26N62W 22N64W TO 20N66W. ISOLATED MODERATE SHOWERS AND POSSIBLE THUNDERSTORMS ARE IN THE ATLANTIC OCEAN FROM 22N TO 31N BETWEEN 51W AND 66W. A SURFACE TROUGH IS ALONG 30N56W 25N62W 20N66W. MIDDLE TO UPPER LEVEL DRY AIR IS EAST OF 32N37W 23N50W 15N60W. A MIDDLE TO UPPER LEVEL TROUGH GOES FROM ONE LOW PRESSURE CENTER NEAR 33N24W TO A SECOND ONE NEAR 28N30W TO A THIRD ONE NEAR 23N42W. BROAD UPPER LEVEL ANTICYCLONIC FLOW COVERS THE REST OF THE ATLANTIC OCEAN NORTH OF 20N. BROAD SURFACE ANTICYCLONIC WIND FLOW IS IN THE ATLANTIC OCEAN ON EITHER SIDE OF THE 30N56W 20N66W TROUGH. $$ MT