000 AXNT20 KNHC 291057 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 805 AM EDT TUE AUG 29 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1045 UTC. ...SPECIAL FEATURE... THE CENTER OF TROPICAL STORM ERNESTO IS NOW BACK OVER WATER NEAR 22.6N 78.9W AT 29/0900 UTC. THIS POSITION IS ABOUT 230 MILES...370 KM...SOUTHEAST OF KEY WEST FLORIDA AND ABOUT 235 MILES...380 KM...SOUTH-SOUTHEAST OF MIAMI FLORIDA. THE ESTIMATED MINIMUM CENTRAL PRESSURE IS 1005 MB. THE MAXIMUM SUSTAINED WIND SPEEDS ARE 40 KT WITH GUSTS TO 50 KT. ERNESTO IS MOVING TOWARD THE NORTHWEST NEAR 12 KT...AND THIS GENERAL MOTION IS EXPECTED TO CONTINUE FOR THE NEXT 24 HOURS. ON THE FORECAST TRACK...THE CENTER OF ERNESTO WILL BE NEAR THE FLORIDA KEYS OR SOUTHEAST FLORIDA BY THIS EVENING. HOWEVER...SQUALLY RAINBANDS WILL BE MOVING ONSHORE THESE AREAS DURING THE AFTERNOON.PLEASE REFER TO THE LATEST NHC FORECAST ADVISORY UNDER HEADERS MIATCMAT5/WTNT25 KNHC AND THE PUBLIC ADVISORY MIATCPAT5/WTNT35 KNHC FOR MORE DETAILS. RADAR IMAGERY FROM MIAMI AND CAMAGUEY CUBA SHOWS NUMEROUS SHOWERS AND TSTMS SPIRALING CYCLONICALLY THROUGH THE FLORIDA STRAITS. SCATTERED MODERATE/ISOLATED STRONG CONVECTION ALSO PERSISTS OVER ERN CUBA AIDED BY UPSLOPE FLOW ON THE SE SEMICIRCLE OF ERNESTO. ...TROPICAL WAVES... A LOW AMPLITUDE TROPICAL WAVE IS ALONG 27W/28W S OF 15N...MOVING W NEAR 15 KT. THIS WAVE IS DIFFICULT TO LOCATE AS IT IS SUPERIMPOSED ON THE MONSOON TROUGH. HOWEVER...BROAD CYCLONIC CURVATURE IS EVIDENT IN NEARBY SURFACE OBSERVATIONS AND LOW TO MID CLOUD MOTIONS ON SATELLITE IMAGERY. A NEW BURST OF SCATTERED MODERATE/ISOLATED STRONG CONVECTION HAS DEVELOPED FROM 11N-13N BETWEEN 25W-29W. A SMALLER CLUSTER IS NOTED NEAR 8N28W. A HIGH AMPLITUDE TROPICAL WAVE IS ALONG 41W S OF 22N MOVING W NEAR 15 KT. A 1010 MB LOW IS ALONG THE WAVE NEAR 17N. BROAD CYCLONIC TURNING REMAINS VERY EVIDENT IN THE LOW TO MID CLOUD FIELD AROUND THE WAVE AXIS AND SURFACE LOW...THOUGH DEEP CONVECTION IS MINIMAL. ...THE ITCZ... ITCZ AXIS IS CENTERED ALONG 13N13W 11N25W 11N30W 13N38W 10N44W TO THE COAST OF SOUTH AMERICA NEAR 9N61W. CLUSTERS OF SCATTERED MODERATE CONVECTION CONTINUE TO MOVE W THROUGH WRN AFRICA AND THE ADJACENT ATLC WATERS FROM FROM 8N-16N BETWEEN 12W-22W...LIKELY ASSOCIATED WITH THE NEXT TROPICAL WAVE. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS FROM 8N-13N BETWEEN 30W-40W. THE WRN HALF OF THE AXIS TO THE SOUTH AMERICAN COAST REMAINS FAIRLY QUIET...THOUGH NUMEROUS STRONG SHOWERS AND TSTMS CONTINUE TO MOVE W THROUGH NW SOUTH AMERICA WHICH IS LIKELY AT LEAST PARTLY ASSOCIATED WITH THE ITCZ. ...DISCUSSION... THE GULF OF MEXICO... ALL EYES REMAIN ON TROPICAL STORM ERNESTO AS THIS SYSTEM WILL HAVE AN IMPACT ON THE WEATHER IN FLORIDA AND THE ERN GULF OVER THE NEXT COUPLE OF DAYS. RAINFALL TOTALS OF 5 TO 10 INCHES ARE POSSIBLE OVER PORTIONS OF EASTERN AND SOUTHERN FLORIDA AND THE KEYS THROUGH WEDNESDAY...WITH ISOLATED AMOUNTS UP TO 15 INCHES POSSIBLE OVER SOUTHEASTERN FLORIDA. FOR MORE INFORMATION REFER TO THE SPECIAL FEATURE SECTION ABOVE. ELSEWHERE IN THE GULF...A CLUSTER OF SCATTERED MODERATE CONVECTION IS SEEN JUST SW OF CAPE SAN BLAS FLORIDA. THIS SEEMS MOST ASSOCIATED WITH UPPER DIFFLUENT AIR BETWEEN THE UPPER HIGH SEEN SPINNING OVER THE SE US AND THE UPPER LOW MOVING W THROUGH THE FLORIDA STRAITS. MID TO UPPER LEVEL CYCLONIC FLOW IS DOMINATING THE WRN HALF OF THE GULF THIS EVENING...AROUND A WELL DEFINED UPPER LOW CENTERED NEAR 23N94W. ISOLATED SHOWERS AND TSTMS CONTINUE TO WRAP AROUND THIS UPPER LOW IN THE WRN GULF. A FAIRLY WEAK SURFACE GRADIENT IS OVER THE GULF...WITH ASSOCIATED LIGHT WINDS AND LOW SEAS BEING OBSERVED. CONSIDERABLY HIGHER WINDS AND SEAS SHOULD BE EXPECTED NEAR ERNESTO. THE CARIBBEAN SEA... THE CENTER OF TROPICAL STORM ERNESTO IS NOW OVER WATER JUST NORTH OF CENTRAL CUBA. THE REMAINDER OF THE CARIBBEAN OUTSIDE OF THE VICINITY OF ERNESTO IS FAIRLY QUIET WITH MINIMAL SHOWER/TSTM ACTIVITY NOTED. DRY/STABLE AIR IS OVER THE FAR NW CARIBBEAN IN ASSOCIATION WITH A WEAK UPPER HIGH IN THE AREA. DRY/STABLE AIR CONTINUES TO BE ADVECTED W INTO THE ERN AND CNTRL CARIBBEAN AROUND THE SRN PERIPHERY OF AN UPPER HIGH. TRADE WINDS ARE A FAIRLY LIGHT 5-15KT ACROSS MUCH OF THE AREA DUE TO A WEAKENING OF THE GRADIENT S OF ERNESTO. THE ATLANTIC OCEAN... A MID-UPPER LEVEL RIDGE CENTERED OVER THE SE US HAS RIDGING THAT STRETCHES E TO 65W ALONG 31N/32N. AN UPPER TROUGH LIES TO THE E OF THE RIDGE BETWEEN 40W-60W MAINLY N OF 20N...WITH AN UPPER LOW CENTER SEEN NEAR 22N57W. A WEAK SURFACE TROUGH/OLD FRONTAL BOUNDARY IS UNDER THIS VICINITY ALONG 26N61W 32N53W....ALONG WITH A PAIR OF WEAK SURFACE LOWS NEAR 30N57W AND 32N51W. CLUSTERS OF MODERATE CONVECTION AND SCATTERED SHOWERS AND TSTMS ASSOCIATED WITH THIS LOW LEVEL CONFLUENT ZONE ARE SEEN FROM 28N-35N BETWEEN 45W-60W. ANOTHER CLUSTER OF MODERATE CONVECTION IS SEEN NEAR 26N45W ASSOCIATED WITH UPPER DIFFLUENCE BETWEEN THE UPPER TROUGH TO THE NORTH...AND AND UPPER HIGH SPINNING ABOUT 500NM ESE OF THE WINDWARD ISLANDS. THE REMAINDER OF THE ATLC IS DOMINATED BY A BROAD UPPER RIDGE EXTENDING FROM AFRICA TO NEAR 50W WITH MULTIPLE HIGH CENTERS. A COUPLE OF WEAK BENIGN UPPER LOWS ARE ON THE W PERIPHERY OF THE RIDGE PRODUCING LITTLE...IF ANY...WEATHER. ANOTHER UPPER LOW CLIPS THE AREA CENTERED JUST OFF THE COAST OF MOROCCO NEAR 31N15W. AT THE SURFACE...A WEAK PRES GRAD EXISTS W OF 50W DUE TO THE WEAK TROUGH DRAPED ACROSS THE NRN PORTION OF THE AREA. STRONGER GRAD IN THE E ATLC AS A 1025 MB HIGH IS CENTERED NE OF THE AZORES INTERACTING WITH A 1011 MB LOW ALONG A TROPICAL WAVE NEAR 17N41W. $$ WILLIS