000 AXNT20 KNHC 081805 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 205 PM EDT SUN JUL 08 2007 TROPICAL WEATHER DISCUSSION FOR NORTH AMERICA...CENTRAL AMERICA...THE GULF OF MEXICO...THE CARIBBEAN SEA...NORTHERN 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...METEOROLOGICAL ANALYSIS... WEATHER OBSERVATIONS...AND RADAR. BASED ON 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1730 UTC. ...TROPICAL WAVES... A TROPICAL WAVE IS ALONG 40W/41W FROM 2N-14N MOVING W NEAR 15 KT. THIS WAVE WAS POSITIONED SLIGHTLY W OF WHERE CONTINUITY WOULD HAVE TAKEN IT...BASED ON THE LOW TO MID LEVEL CYCLONIC TURNING NOTED FROM 9N-14N BETWEEN 37W-43W...AND THE SURGE OF SCATTERED SHOWERS/TSTMS FROM 2N-9N BETWEEN 39W-45W. DEEP CONVECTION REMAINS MINIMAL THOUGH. CONVECTION HAS FLARED UP FURTHER W ALONG THE ITCZ BETWEEN 49W-57W AS DISCUSSED BELOW. BASED ON SATELLITE HOVMOLLER DIAGRAMS...THERE MAY BE ANOTHER WEAK TROPICAL WAVE IN THE VICINITY OF 51W WHICH WILL BE REEVALUATED FOR THE 1800 UTC MAP. A TROPICAL WAVE IS ALONG 65W SOUTH OF 15N MOVING W 10-15 KT. THIS WAVE HAS LOST MUCH OF ITS IDENTITY OVER THE LAST COUPLE OF DAYS...AND NOW IS MAINLY JUST A SURGE OF MOISTURE AS DEPICTED WELL BY SSMI DERIVED PRECIPITABLE WATER. DEEP CONVECTION REMAINS MINIMAL ON BOTH SIDES OF THE AXIS. A TROPICAL WAVE IN THE CARIBBEAN IS ALONG 81W MOVING W NEAR 15 KT. SCATTERED SHOWERS AND TSTMS...ALSO ENHANCED BY THE ITCZ...ARE OVER THE SW CARIBBEAN AND CENTRAL AMERICA S OF 13N. LOW CLOUD MOTIONS SHOW SOME CYCLONIC TURNING S OF CUBA...N OF 17N BETWEEN 78W-84W...BUT AM NOT ENTIRELY CONVINCED THIS IS DUE TO THE WAVE. REGARDLESS...LIGHTNING DATA SUPPORTS ISOLATED TSTMS IN THIS REGION. ...THE ITCZ... ITCZ AXIS IS CENTERED ALONG 8N11W 5N25W 8N38W 9N50W 7N60W. ISOLATED MODERATE CONVECTION IS WITHIN 90NM EITHER SIDE OF THE AXIS E OF 15W...AND BETWEEN 19W-29W. AS MENTIONED ABOVE...SCATTERED MODERATE IS WITHIN 90NM OF THE AXIS BETWEEN 48W-59W. ...DISCUSSION... GULF OF MEXICO... A WEAK 1017 MB HIGH IS OVER THE CENTRAL GULF NEAR 26N88W. THIS IS EXPECTED TO CONTINUE DISSIPATING THROUGH TONIGHT AS THE WRN PORTION OF THE ATLC RIDGE BUILDS W. HOWEVER...LEFTOVER LOW LEVEL CONFLUENCE BETWEEN THE TWO HIGHS IS PRODUCING WEAK TROUGHING IN THE SE GULF. THIS WAS PLACED ALONG 25N82W 23N88W AT 8/1500 UTC...AND IS SUPPORTING SCATTERED SHOWERS/ISOLATED TSTMS WITHIN 60NM EITHER SIDE OF THE TROUGH. THIS ACTIVITY ALSO AIDED BY UPPER DIFFLUENCE BETWEEN AN UPPER HIGH JUST W OF TAMPA AND BROAD TROUGHING IN THE CARIBBEAN. A PAIR OF THIN LINES OF LOW CLOUDS ARE JUST S OF THE FL PANHANDLE...ASSOCIATED WITH LOW LEVEL CONFLUENCE S AND AHEAD OF THE LOW SPINNING OVER ALABAMA/GEORGIA. FAIR WEATHER AND LIGHT TO MODERATE WINDS AROUND RIDGING DOMINATE ELSEWHERE. CARIBBEAN SEA... OUTSIDE OF THE WEATHER MENTIONED ABOVE WITH THE TROPICAL WAVES THE BASIN IS FAIRLY QUIET. MODERATE TO FRESH TRADES ARE IN PLACE S OF AN ATLC SFC RIDGE...AND EXPECTED TO PERSIST THROUGH MIDWEEK. THE TRADES ARE ALLOWING TYPICAL PATCHES OF LOW LEVEL MOISTURE WITH EMBEDDED ISOLATED SHOWERS TO PUSH W ACROSS THE AREA. THE UPPER PATTERN IS LARGELY DOMINATED BY ELONGATED TROUGHING THAT EXTENDS E/W ALONG 15/16N. ATLANTIC OCEAN... AN AREA OF SCATTERED SHOWERS/TSTMS REMAINS OFF THE FLORIDA COAST...WITHIN 120NM EITHER SIDE OF A LINE FROM PALM BEACH TO 32N74W. IN ADDITION TO THE LOW LEVEL CONFLUENCE THAT HAS HUNG AROUND IN THIS VICINITY THE LAST FEW DAYS...THE ACTIVITY IS BEING SUPPORTED BY UPPER DIFFLUENCE AROUND AN UPPER RIDGE AXIS. THE REMAINDER OF THE DISCUSSION AREA IS BY AND LARGE DOMINATED BY A TYPICAL SUMMERTIME SFC RIDGE AXIS ANCHORED BY A 1032MB HIGH NEAR 42N22W. THIS IS PRODUCING ABUNDANT FAIR WEATHER AND LIGHT TO MODERATE TRADES E OF 70W. THE WEAK TROUGHING/LOW LEVEL CONFLUENCE OVER THE WRN ATLC WILL GRADUALLY DISSIPATE/LIFT NE OVER THE NEXT DAY OR SO AS THE ATLC RIDGE BUILDS W ACROSS FLORIDA AND INTO THE GULF. ELSEWHERE ALOFT ON THE LARGE SCALE...RIDGING CONTINUES TO DOMINATE THE FAR W AND E PORTIONS OF THE DISCUSSION AREA WITH BROAD TROUGHING OVER THE CENTRAL ATLC. OTHER SMALLER SCALE UPPER FEATURES ARE EMBEDDED IN THIS PATTERN BUT ARE NOT GENERATING SIGNIFICANT WEATHER. $$ WILLIS