000 AXNT20 KNHC 272345 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 805 PM EDT FRI JUN 27 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 1715 UTC. ...TROPICAL WAVES... A WEAK TROPICAL WAVE IS ALONG 25W S OF 14N MOVING W AT 20 KT. THE SCATTERED MODERATE CONVECTION THAT WAS ACCOMPANYING THE WAVE EARLIER IS WANING SIGNIFICANTLY...BUT THERE REMAINS A REGION OF MORE ORGANIZED CONVECTION AROUND 25W BETWEEN 2N AND 4N. A TROPICAL WAVE ALONG 37W S OF 12N IS MOVING W AT 15-20 KT. A BROAD MID TO LOW LEVEL CIRCULATION IS NOTED ON INFRARED SATELLITE IMAGERY AND WIDESPREAD DEEP CONVECTION CAN BE FOUND E OF THE WAVE IN THE REGION WITHIN 11N34W TO 6N29W. A TROPICAL WAVE HAS BEEN ADDED ALONG 50W S OF 13N. THE LACK OF DEEP CONVECTION WITH THIS WAVE HAS MADE IT DIFFICULT TO TRACK... BUT THE WAVE WAS IDENTIFIED BASED ON AN EVIDENT LOW LEVEL CIRCULATION NOTED ON VISIBLE SATELLITE IMAGERY CENTERED AROUND 9N50W IN ADDITION TO THE ASCAT PASS AROUND 1240Z THAT SHOWED A DISTINCT TURNING IN THE WIND FIELD IN ADVANCE 0F THE WAVE. THE FEATURE COULD BE TRACKED BACK ON THE HOVMOLLER DIAGRAM FROM 1145Z/25 THROUGH 1145Z THIS MORNING. IN ADDITION...THE CIMSS MIMIC-TPW PRODUCT ALSO SHOWS A DISTINCT NORTHWARD SURGE IN ATMOSPHERIC MOISTURE WITH THIS WAVE. THE INITIAL ESTIMATE OF THE FORWARD MOTION IS W AT 15 KT. A WEAK TROPICAL WAVE APPEARS TO HAVE PASSED THROUGH TRINIDAD AND TOBAGO THIS EVENING ACCORDING TO SFC OBS. THE WAVE LIES MAINLY S OF 13 BETWEEN 61W AND 62W AND IS MOVING W AT 20 KT. CONVECTION WITH THIS WAVE IS WIDELY SCATTERED AND LIES PRIMARILY OFF THE NORTHEASTERN VENEZUELA COAST BETWEEN CARACAS AND GRENADA. A TROPICAL WAVE ALONG 91W S OF 22N HAS MOVED THROUGH THE YUCATAN PENINSULA AND NOW LIES MAINLY IN THE EASTERN PACIFIC OCEAN. HOWEVER...SIGNIFICANT CONVECTION ASSOCIATED WITH THE WAVE CAN BE FOUND IN THE CENTRAL GULF OF MEXICO BETWEEN 27N95W AND 24N87W AS WELL AS OFF THE NORTHERN YUCATAN PENINSULA S OF 23N. PLEASE SEE THE EASTERN PACIFIC TROPICAL WEATHER DISCUSSION...TWDEP...FOR FURTHER DETAILS ON THIS WAVE. ...ITCZ... THE ITCZ AXIS IS CENTERED ALONG 10N16W 10N22W 8N35W 5N42W AND INTO NORTHEASTERN SOUTH AMERICA NEAR 4N51W. IN ADDITION TO CONVECTION ASSOCIATED WITH TROPICAL WAVES...SCATTERED MODERATE TO STRONG CONVECTION IS MOVING OFF THE WEST AFRICAN COAST TO 19W FROM 9N-14N. SCATTERED MODERATE CONVECTION CAN BE FOUND OFF THE NORTHEASTERN BRAZIL COAST S OF THE LINE FROM 3N41W TO 5S29W...WITH MORE VIGOROUS CONVECTION FOUND ON THE EASTERN EDGE OF THAT REGION SE AND S OF ILHA FERNANDO DE NORONHA. ...DISCUSSION... GULF OF MEXICO... A HIGHLY AMPLIFIED UPPER PATTERN OVER THE GULF OF MEXICO IS MARKED BY A LOW OVER THE WESTERN GULF AND A RIDGE OVER THE EASTERN GULF. AT THE SURFACE...THE WESTERN EDGE OF THE CENTRAL NORTH ATLC RIDGE EXTENDS INTO THE EASTERN GULF WHILE A LOW PRESSURE TROUGH MOVING INTO THE SOUTHERN PLAINS IS INDUCING SOUTHEASTERLY GULF RETURN FLOW INTO THE TEXAS COAST. AS A RESULT...DEEP SOUTHERLY FLOW DOMINATES THE CENTRAL GULF AND IS HELPING TO SUPPLY MOISTURE...IN CONJUNCTION WITH THE NORTHERN EDGE OF THE TROPICAL WAVE PASSING THROUGH SOUTHERN MEXICO...TO THE DEEP CONVECTION FOUND IN THE CENTRAL GULF BETWEEN 27N95W AND 24N87W AS WELL AS OFF THE NORTHERN YUCATAN PENINSULA S OF 23N. THE MOST ORGANIZED AND VIGOROUS CONVECTION CAN BE FOUND WITHIN THE REGION OF UPPER LEVEL DIVERGENT FLOW IN THE GULF FOUND BETWEEN 85W AND 90W. ELSEWHERE...ISOLATED THUNDERSTORMS CAN BE FOUND NEAR THE CENTRAL GULF COAST BETWEEN BILOXI...MISSISSIPPI AND APALACHICOLA...FLORIDA. CARIBBEAN... STRONG EASTERLY TRADE WINDS ON THE SOUTHERN EDGE OF THE SUBTROPICAL RIDGE CENTERED ALONG 28N DOMINATES THE LOW LEVEL PATTERN IN THE CARIBBEAN. RELATIVELY DRY CONDITIONS AND UPPER LEVEL CONVERGENCE OVER THE CENTRAL CARIBBEAN ARE SUPPRESSING CONVECTION OVER MUCH OF THE REGION. THE TROPICAL WAVE BETWEEN 61W AND 62W IS GENERATING LITTLE SENSIBLE WEATHER...WITH ONLY WIDELY SCATTERED SHOWERS AND THUNDERSTORMS PRIMARILY OFF THE NORTHEASTERN VENEZUELA COAST BETWEEN CARACAS AND GRENADA. MORE VIGOROUS CONVECTION CAN BE FOUND IN THE FAR SOUTHEASTERN CARIBBEAN OFF THE SOUTHERN COSTA RICA AND PANAMANIAN COAST WHERE DEEP MOISTURE IS MORE PLENTIFUL AND SPEED DIVERGENCE ALOFT IS INITIATING LIFT. UNORGANIZED...SCATTERED CONVECTION CAN ALSO BE FOUND OFF THE SOUTHEASTERN JAMAICAN COAST AND WITHIN THE JAMAICA CHANNEL EXTENDING NORTHWARD TO THE SOUTHEASTERN CUBAN COAST. ATLANTIC... THE SUBTROPICAL HIGH PRESSURE AT THE SURFACE CONTINUES TO DOMINATE THE LOW LEVEL FLOW ACROSS THE ATLC...WITH EASTERLY TRADE WINDS FOUND NORTH AND WEST OF 10N30W AND FLOW GENERALLY TURNING MORE N TO NE TO THE EAST OF THIS LOCATION. OFF THE WESTERN AFRICAN COAST...SCATTERED MODERATE TO STRONG CONVECTION IS MOVING OFFSHORE TO 19W FROM 9N-14N. TO THE EAST...TWO TROPICAL WAVES ARE EMBEDDED WITHIN THE ITCZ...ONE AT 26W AND ANOTHER AT 37W. THE BEST DIVERGENCE ALOFT LIES BETWEEN THE TWO WAVES NEAR 31N...WITH AN AREA OF MODERATE CONVECTION FOUND IN THE REGION WITHIN 11N34W TO 6N29W. FARTHER EAST...ANOTHER TROPICAL WAVE INTRODUCED ALONG 50W IS GENERATING LITTLE CONVECTION. ELSEWHERE...SCATTERED MODERATE CONVECTION CAN BE FOUND OFF THE NORTHEASTERN BRAZIL COAST S OF THE LINE FROM 3N41W TO 5S29W...WITH MORE VIGOROUS CONVECTION FOUND ON THE EASTERN EDGE OF THAT REGION SE AND S OF ILHA FERNANDO DE NORONHA. ANOTHER AREA OF MODERATE CONVECTION CAN BE FOUND BETWEEN THE TROPICAL WAVES AT 50W AND 61-62W WITHIN THE DIVERGENT FLOW BETWEEN THE UPPER LEVEL CYCLONE AT 23N66W AND THE UPPER LEVEL ANTICYCLONE NEAR 14N50W. OFF THE EASTERN FLORIDA COAST...LOOK FOR AFTERNOON THUNDERSTORMS BEING STEERED EASTWARD OFF THE PENINSULA TO WEAKEN AS THEY PASS OFFSHORE AROUND SAINT AUGUSTINE AND FORT PIERCE. $$ SCHAUER CLARK