000 AXNT20 KNHC 071044 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 805 AM EDT FRI AUG 07 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1015 UTC. ...TROPICAL WAVES... AN ATLANTIC OCEAN TROPICAL WAVE IS ALONG 34W TO THE SOUTH OF 17N MOVING WESTWARD 10 TO 15 KT. LINGERING ISOLATED SHOWERS FROM 13N TO 15N BETWEEN 34W AND 38W. AN ATLANTIC OCEAN TROPICAL WAVE IS ALONG 51W/52W TO THE SOUTH OF 15N MOVING WESTWARD 15 TO 20 KT. NEARBY ITCZ PRECIPITATION. AN EASTERN CARIBBEAN SEA TROPICAL WAVE IS ALONG 68W/69W FROM 20N SOUTHWARD THROUGH THE MONA PASSAGE INTO NORTHWESTERN COASTAL VENEZUELA...MOVING WESTWARD ABOUT 15 KT. THIS WAVE IS MOVING TOWARD THE AREA THAT ALREADY IS COVERED BY AN UPPER LEVEL TROUGH WHOSE BASE REACHES NORTHERN COASTAL COLOMBIA...AND THE BASE OF A DIFFERENT UPPER LEVEL TROUGH THAT REACHES THE EASTERN SECTIONS OF THE DOMINICAN REPUBLIC. NO SIGNIFICANT DEEP CONVECTIVE PRECIPITATION JUST ACCOMPANIES ONLY THE TROPICAL WAVE. A WESTERN CARIBBEAN SEA TROPICAL WAVE IS ALONG 85W/86W FROM THE YUCATAN CHANNEL SOUTHWARD INTO NICARAGUA...MOVING WESTWARD ABOUT 15 KT. IT IS NOT EASY TO FIND SIGNIFICANT DEEP CONVECTIVE PRECIPITATION THAT JUST ACCOMPANIES ONLY THE TROPICAL WAVE. SOME PRECIPITATION IS IN THE SOUTHWESTERN CORNER OF THE CARIBBEAN SEA...IN UPPER LEVEL DIFFLUENT WIND FLOW. ...THE ITCZ... FROM THE AFRICA COAST NEAR 11N15W TO 15N38W 11N56W. WHAT APPEARS TO BE A SECOND ITCZ...AND/OR A SECOND OF LINE OF SURFACE CONFLUENT WIND FLOW...IS TO THE SOUTH OF THE FIRST ONE ALONG 10N14W 9N23W 7N34W 7N41W 7N50W 6N56W. IT IS INTERESTING TO NOTE THAT THE LAST VISIBLE SATELLITE IMAGES FROM YESTERDAY CLEARLY SHOW THAT THE WIND FLOW FROM THE EQUATOR NORTHWARD BLOWS RIGHT PAST THE 10N14W 6N56W LINE TOWARD THE 11N15W 11N56W LINE...GIVING THE IMPRESSION THAT THE NORTHERN-MORE LINE IS THE ITCZ. STRONG SHOWERS AND THUNDERSTORMS ARE IN CLUSTERS FROM 10N TO 13N BETWEEN 44W AND 57W. SCATTERED MODERATE SHOWERS TO ISOLATED STRONG THUNDERSTORMS ARE FROM 6N TO 8N BETWEEN 48W AND 53W. ISOLATED MODERATE SHOWERS AND POSSIBLE THUNDERSTORMS ARE ELSEWHERE FROM 6N TO 11N BETWEEN AFRICA AND 44W. STRONG SHOWERS AND THUNDERSTORMS ARE IN THE COASTAL WATERS OF AFRICA FROM 13N TO 17N...POSSIBLY/PROBABLY WITH THE NEXT TROPICAL WAVE. ...DISCUSSION... THE GULF OF MEXICO... AN UPPER LEVEL TROUGH EXTENDS FROM A 24N92W TO 19N99W INLAND IN SOUTH CENTRAL MEXICO. SHOWERS ARE WITHIN 60 NM TO 120 NM ON EITHER SIDE OF THE TROUGH. THIS TROUGH IS IN THE MIDDLE OF TWO SEPARATE AREAS OF UPPER LEVEL ANTICYCLONIC FLOW. A SURFACE TROUGH PASSES THROUGH NORTH CENTRAL FLORIDA TO 28N85W TO 24N87W INTO THE NORTHERN YUCATAN PENINSULA. ISOLATED MODERATE SHOWERS ARE TO THE SOUTH OF 29N TO THE EAST OF 86W. EARLIER PRECIPITATION IN INTERIOR MEXICO HAS BEEN DISSIPATING DURING THE LAST SIX HOURS. THE CARIBBEAN SEA... THE MODERATE TO STRONG SHOWERS AND THUNDERSTORMS IN EL SALVADOR SIX HOURS NOW ONLY ARE IN ITS COASTAL WATERS...IN BROAD SURFACE LOW PRESSURE AND UPPER LEVEL DIFFLUENT FLOW. ONE TROPICAL WAVE IS ALONG 68W/69W...AND A SECOND ONE IS ALONG 85W/86W. IT DOES NOT APPEAR THAT EITHER WAVE IS ACCOMPANIED BY MUCH PRECIPITATION. ONE UPPER LEVEL TROUGH RUNS FROM 16N77W TO NORTHERN COASTAL COLOMBIA. NUMEROUS STRONG SHOWERS AND THUNDERSTORMS ARE IN NORTHERN COLOMBIA AND THE GULF OF URABA FROM 7N TO 10N BETWEEN 75W AND 79W. THE LAKE MARACAIBO PRECIPITATION FROM SIX HOURS AGO HAS DISSIPATED. A PERSISTENT UPPER LEVEL TROUGH PASSES THROUGH 25N67W OF THE ATLANTIC OCEAN TO EASTERN SECTIONS OF THE DOMINICAN REPUBLIC. SHOWERS ARE POSSIBLE FROM THE NORTHEASTERN ISLANDS TO 20N BETWEEN 60W AND 70W...UNDER THE PERSISTENT UPPER LEVEL CYCLONIC FLOW AROUND THE TROUGH. FROM THE WESTERN ATLANTIC OCEAN INTO THE EASTERN CARIBBEAN SEA.. A PERSISTENT UPPER LEVEL TROUGH GOES BERMUDA TO 25N67W TO EASTERN SECTIONS OF THE DOMINICAN REPUBLIC. SHOWERS AND POSSIBLE THUNDERSTORMS WILL CONTINUE TO BE POSSIBILITY TO THE NORTH OF 20N BETWEEN 60W AND 73W. A SURFACE TROUGH IS ALONG 29N72W 22N74W. THIS TROUGH USED TO BE THE NORTHERN EXTENSION OF THE MONA PASSAGE/CARIBBEAN SEA TROPICAL WAVE. THE REST OF THE ATLANTIC OCEAN... AN UPPER LEVEL RIDGE GOES FROM SOUTHEASTERN CUBA TO 26N78W IN THE PROVIDENCE CHANNEL...IN BETWEEN ANDROS ISLAND AND GRAND BAHAMA AND ABACO ISLAND OF THE BAHAMAS...BEYOND 32N79W. AN UPPER LEVEL TROUGH EXTENDS FROM A CYCLONIC CIRCULATION CENTER THAT IS NEAR 28N39W TO 19N48W. ISOLATED MODERATE SHOWERS FROM 25N TO 31N BETWEEN 41W AND 46W. $$ MT