000 AXNT20 KNHC 112203 CCA TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 205 PM EDT MON MON 11 2006 CORRECTED FOR DATE 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1745 UTC. ...SPECIAL FEATURES... THE CENTER OF HURRICANE FLORENCE AT 11/1800 UTC IS NEAR 33.6N 65.3W. THIS POSITION IS ALSO ABOUT 80 NM/145 KM NORTH-NORTHWEST OF BERMUDA. HURRICANE FLORENCE IS MOVING NORTH-NORTHEAST 11 KT. THIS MOTION IS EXPECTED TO CONTINUE WITH SOME INCREASE IN FORWARD SPEED DURING THE NEXT 24 HOURS. THE CENTER OF FLORENCE IS EXPECTED TO MOVE AWAY FROM BERMUDA LATER TODAY. THE MAXIMUM SUSTAINED WIND SPEEDS ARE 80 KT WITH GUSTS TO 100 KT. FLORENCE IS A CATEGORY ONE HURRICANE ON THE SAFFIR-SIMPSON SCALE. NO SIGNIFICANT CHANGE IN STRENGTH IS EXPECTED THROUGH TONIGHT. AN ELEVATED OBSERVING SITE IN BERMUDA RECENTLY REPORTED A WIND GUST TO 111 MPH/179 KM/HR. HURRICANE FORCE WINDS EXTEND OUTWARD UP TO 60 NM/110 KM FROM THE CENTER...AND TROPICAL STORM FORCE WINDS EXTEND OUTWARD UP TO 250 NM/465 KM. THE ESTIMATED MINIMUM CENTRAL PRESSURE IS 972 MB. STORM SURGE VALUES OF 6 TO 8 FEET ABOVE NORMAL TIDE LEVELS ALONG WITH LARGE AND DANGEROUS BATTERING WAVES ARE LIKELY ALONG THE COAST OF BERMUDA TODAY. THESE CONDITIONS ARE EXPECTED TO BEGIN SUBSIDING TONIGHT. LARGE OCEAN SWELLS AND DANGEROUS SURF CONDITIONS...INCLUDING STRONG RIP CURRENTS...ARE AFFECTING THE BAHAMAS AND SECTIONS OF THE EAST COAST OF THE UNITED STATES AND THE CANADIAN MARITIMES. PLEASE READ STATEMENTS FROM LOCAL WEATHER SERVICE OFFICES FOR DETAILS ON COASTAL CONDITIONS. PLEASE READ THE LATEST NHC FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMAT1/WTNT21 KNHC OR THE PUBLIC ADVISORY UNDER MIATCPAT1/WTNT31 KNHC FOR MORE DETAILS. NUMEROUS STRONG SHOWERS AND THUNDERSTORMS FROM 32N TO 34N BETWEEN 64W AND 66W. CLOUD TOP TEMPERATURES RANGING FROM -72C TO -79C WERE FROM 31N TO 35N BETWEEN 64W AND 68W AT 11/1215 UTC. THE CLOUD TOP TEMPERATURES IN THE AREA FROM 31N TO 35N BETWEEN 64W AND 67W ONLY RANGE FROM -60C TO -65C...EXCEPT FOR THE PART OF THE STRONG SHOWERS AND THUNDERSTORMS. IT IS EASILY POSSIBLE TO FIND SOME FORM OF STRONG PRECIPITATION FOR ANOTHER 200 NM IN THE NORTHERN SEMICIRCLE OF THIS SYSTEM. THE CENTER OF TROPICAL DEPRESSION SEVEN AT 11/1500 UTC IS NEAR 21.1N 56.7W. THIS POSITION ALSO IS ABOUT 380 NM/700 KM NORTHEAST OF THE LEEWARD ISLANDS. IT IS MOVING WEST-NORTHWEST 8 KT. THE ESTIMATED MINIMUM CENTRAL PRESSURE IS 1009 MB. THE MAXIMUM SUSTAINED WIND SPEEDS ARE 30 KT WITH GUSTS TO 40 KT. PLEASE READ THE LATEST NHC FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMAT2/WTNT22 KNHC AND THE PUBLIC ADVISORY MIATCPAT2/WTNT32 KNHC FOR MORE DETAILS. THE DEPRESSION MAY BECOME A TROPICAL STORM LATER TODAY. AN AIR FORCE RESERVE UNIT RECONNAISSANCE PLANE IS SCHEDULED TO INVESTIGATE THE SYSTEM TODAY. SCATTERED MODERATE SHOWERS TO ISOLATED STRONG THUNDERSTORMS FROM 18N TO 27N BETWEEN 53W AND 60W. A 1009 MB LOW PRESSURE CENTER IS NEAR 13N14W IN SOUTHERN SENEGAL IN THE PART OF THE COUNTRY BETWEEN GAMBIA AND GUINEA-BISSAU. IT IS FORECAST TO ENTER THE ATLANTIC OCEAN DURING THE NEXT 24 HOURS. DEVELOPMENT OF THIS SYSTEM IS POSSIBLE DURING THE NEXT DAY OR TWO AS IT MOVES WESTWARD OVER THE FAR EASTERN TROPICAL ATLANTIC OCEAN. THE COLDER CLOUD TOP TEMPERATURE SCENARIO WAS MUCH MORE IMPRESSIVE 4 TO 5 HOURS AGO. TEMPERATURES HAVE WARMED...BUT PRECIPITATION PROBABLY REMAINS STILL...FROM 9N TO 16N BETWEEN 12W AND 21W. ...TROPICAL WAVES... AN ATLANTIC OCEAN TROPICAL WAVE IS ALONG 30W/31W SOUTH OF 19N MOVING WEST 10 TO 15 KT. ANY FORM OF PRECIPITATION IS IN THE ITCZ AT THIS MOMENT. AN ATLANTIC OCEAN TROPICAL WAVE IS ALONG 42W/43W SOUTH OF 13N MOVING WEST 10 TO 15 KT. ANY FORM OF PRECIPITATION IS IN THE ITCZ AT THIS MOMENT FROM 10N TO 13N BETWEEN 40W AND 50W. AN ATLANTIC OCEAN TROPICAL WAVE IS ALONG 57W/58W SOUTH OF 16N MOVING WEST 10 TO 15 KT. THIS WAVE HAS CONTINUED TO MOVE TO THE WEST...AS TROPICAL DEPRESSION SEVEN BECOMES ITS OWN ENTITY. ISOLATED MODERATE SHOWERS AND POSSIBLE THUNDERSTORMS IN THE ITCZ FROM 10N TO 13N BETWEEN 50W AND 62W. TROPICAL WAVE ALONG 96W/97W SOUTH OF 20N MOVING WEST 10-15 KT. NO DEEP CONVECTIVE PRECIPITATION WITH THIS WAVE. A FEW CELLS OF STRONG THUNDERSTORMS FROM 17N TO 18N BETWEEN 95W AND 96W. A MIDDLE TO UPPER LEVEL TROUGH RUNS FROM A WEST-CENTRAL YUCATAN PENINSULA LOW PRESSURE CENTER TO A LOW PRESSURE CENTER IN INTERIOR MEXICO JUST WEST OF THE ISTHMUS OF TEHUANTEPEC. MIDDLE LEVEL NORTHEASTERLY FLOW IS UNDERCUTTING UPPER LEVEL ANTICYCLONIC FLOW OVER THE WAVE. ...THE ITCZ... ITCZ 11N14W 8N24W 8N28W 8N32W 9N41W 10N45W 9N55W. SCATTERED MODERATE SHOWERS AND ISOLATED THUNDERSTORMS FROM 6N TO 10N BETWEEN AFRICA AND 20W...FROM 4N TO 10N BETWEEN AND 45W...FROM 10N TO 13N BETWEEN 40W AND 50W. ISOLATED MODERATE SHOWERS AND POSSIBLE THUNDERSTORMS FROM 10N TO 13N BETWEEN 50W AND 62W. ...DISCUSSION... THE GULF OF MEXICO... AN UPPER LEVEL RIDGE STARTS AT A HIGH PRESSURE CENTER NEAR 27N103W IN INTERIOR MEXICO. THE RIDGE CONTINUES TO THE UPPER TEXAS COAST...TO SOUTHEASTERN LOUISIANA...TO NORTHEASTERN FLORIDA ALONG 30N...TO 28N75W. UPPER LEVEL ANTICYCLONIC FLOW COVERS THE GULF WATERS TO THE NORTHWEST OF 26N82W 25N90W 22N98W. A MIDDLE TO UPPER LEVEL TROUGH RUNS FROM A WEST-CENTRAL YUCATAN PENINSULA LOW PRESSURE CENTER TO A LOW PRESSURE CENTER IN INTERIOR MEXICO JUST WEST OF THE ISTHMUS OF TEHUANTEPEC. MIDDLE TO UPPER LEVEL WESTERLY FLOW MOVES ALONG 30N BETWEEN 80W AND 100W. ISOLATED MODERATE SHOWERS TO LOCALLY STRONG THUNDERSTORMS ARE SOUTH OF 23N WEST OF 87W. SHOWERS AND THUNDERSTORMS NORTH OF 23N BETWEEN FLORIDA AND SOUTH CENTRAL TEXAS ARE IN AN AREA OF UPPER LEVEL DIFFLUENT FLOW...AND UNDER THE UPPER LEVEL RIDGE. THE CARIBBEAN SEA... UPPER LEVEL ANTICYCLONIC FLOW COVERS THE AREA. THE EASTERN END OF AN UPPER LEVEL RIDGE IS SITUATED TO THE WEST AND SOUTHWEST OF THE FLOW AROUND HURRICANE FLORENCE. A MIDDLE TO UPPER LEVEL LOW PRESSURE CENTER IS ALONG THE PANAMA/COSTA RICA BORDER. BROAD CYCLONIC FLOW COVERS THE SOUTHWESTERN CORNER OF THE AREA... INCLUDING EXTREME NORTHWESTERN COLOMBIA/PANAMA/COSTA RICA/ SOUTHEASTERN NICARAGUA. UPPER LEVEL MOISTURE COVERS THE CARIBBEAN SEA EAST OF 73W. MIDDLE TO UPPER LEVEL DRY AIR IS ELSEWHERE BETWEEN 73W AND 83W. CLOUDS AND ISOLATED MODERATE SHOWERS ARE IN THE NORTHWESTERN CORNER AROUND THE WEST-CENTRAL YUCATAN PENINSULA LOW PRESSURE CENTER. THE ATLANTIC OCEAN... SOME OF THE MIDDLE TO UPPER LEVEL WESTERLY FLOW ALONG 30N AND EXITING FLORIDA CURVES TOWARD A TROUGH BASE...AND IMPARTS UPPER LEVEL SOUTHWESTERLY SHEAR ON HURRICANE FLORENCE. THE REST OF THE FLOW CURVES TOWARD THE SOUTH AND EVENTUAL ANTICYCLONIC FLOW. THE ANTICYCLONIC FLOW COVERS THE ATLANTIC OCEAN NORTH OF 20N BETWEEN 70W AND FLORIDA. A MIDDLE TO UPPER LEVEL LOW PRESSURE CENTER HAS FORMED/IS FORMING NEAR 24N62W. A MIDDLE TO UPPER LEVEL TROUGH GOES FROM A WELL DEFINED LOW PRESSURE CENTER NEAR 28N38W TO 27N49W AND 28N56W. ANOTHER TROUGH GOES FROM THE 28N38W LOW CENTER TO 20N42W AND 14N50W. SURFACE ANTICYCLONIC WIND FLOW COVERS THE ATLANTIC OCEAN WATERS NORTH OF THE TROPICAL WAVES BETWEEN AFRICA AND 50W. A MIDDLE TO UPPER LEVEL LOW PRESSURE CENTER IS NEAR 15N22W JUST EAST OF THE CAPE VERDE ISLANDS. $$ MT