000 AXNT20 KNHC 120005 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 805 PM EDT MON MON 11 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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 2345 UTC. ...SPECIAL FEATURES... THE CENTER OF HURRICANE FLORENCE AT 12/0000 UTC WAS LOCATED NEAR LATITUDE 35.2 NORTH...LONGITUDE 64.4 WEST OR ABOUT 195 MILES...315 KM...NORTH OF BERMUDA. FLORENCE IS MOVING TOWARD THE NORTH-NORTHEAST NEAR 16 MPH...26 KM/HR. THIS GENERAL MOTION WITH SOME INCREASE IN FORWARD SPEED IS EXPECTED DURING THE NEXT 24 HOURS. THE ESTIMATED MINIMUM CENTRAL PRESSURE IS 974 MB. MAXIMUM SUSTAINED WINDS HAVE DECREASED TO NEAR 85 MPH...140 KM/HR...WITH HIGHER GUSTS. FLORENCE IS A CATEGORY ONE HURRICANE ON THE SAFFIR-SIMPSON SCALE. FURTHER WEAKENING IS LIKELY OVERNIGHT. 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. FLORENCE IS A LARGE HURRICANE. HURRICANE FORCE WINDS EXTEND OUTWARD UP TO 70 MILES...110 KM...FROM THE CENTER...AND TROPICAL STORM FORCE WINDS EXTEND OUTWARD UP TO 290 MILES...465 KM. WINDS AT BERMUDA WILL CONTINUE TO DECREASE THIS EVENING. THE CENTER OF RECENTLY UPGRADED TROPICAL STORM GORDON AT 11/2100 UTC IS NEAR 21.6N 57.3W. THIS POSITION ALSO IS ABOUT 425 MILES/690 KM NORTHEAST OF THE LEEWARD ISLANDS. GORDON IS MOVING TOWARD THE NORTHWEST NEAR 9 MPH...15 KM/HR...AND THIS MOTION IS EXPECTED TO CONTINUE FOR THE NEXT 24 HOURS.THE ESTIMATED MINIMUM CENTRAL PRESSURE IS 1003 MB. MAXIMUM SUSTAINED WINDS ARE NEAR 45 MPH...75 KM/HR...WITH HIGHER GUSTS. ADDITIONAL STRENGTHENING IS FORECAST DURING THE NEXT 24 HOURS. PLEASE READ THE LATEST NHC FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMAT2/WTNT22 KNHC AND THE PUBLIC ADVISORY MIATCPAT2/WTNT32 KNHC FOR MORE DETAILS. A 1008 MB LOW PRESSURE CENTER NEAR 12N17W IS EMERGING OFF THE COAST OF AFRICA. DEVELOPMENT OF THIS SYSTEM IS POSSIBLE DURING THE NEXT DAY OR TWO AS IT MOVES WESTWARD OVER THE FAR EASTERN TROPICAL ATLANTIC. A CLUSTER OF SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS SEEN FROM 7N-10N BETWEEN 16W-24W. ...TROPICAL WAVES... AN ATLANTIC OCEAN TROPICAL WAVE IS ALONG 31W/32W SOUTH OF 18N MOVING WEST NEAR 10 KT. PRECIPITATION AND CLOUDINESS ASSOCIATED WITH THIS WAVE IS MOSTLY CONFINED TO THE ITCZ...THOUGH SOME LOW TO MID CLOUD CYCLONIC TURNING IS STILL NOTED N OF 12N. THE PLACEMENT OF THIS WAVE (ALONG WITH THE SPECIAL FEATURE MOVING OFF AFRICA) IS OBVIOUS AFTER VIEWING A METEOSAT8 HOVMOLLER DIAGRAM. A LOW AMPLITUDE ATLANTIC OCEAN TROPICAL WAVE IS ALONG 43W/44W SOUTH OF 16N MOVING WEST NEAR 10 KT. THE PLACEMENT OF THIS WAVE REMAINS DIFFICULT WITH CONVECTION FROM THE ITCZ...ALONG WITH MID TO UPPER LEVEL SW FLOW...OBSCURING THE SIGNAL. SCATTERED SHOWERS AND TSTMS FROM 7N-16N BETWEEN 40W-50W BETWEEN 1800-1900 UTC ARE NOW BECOMING MORE ISOLATED IN NATURE. AN ATLANTIC OCEAN TROPICAL WAVE IS ALONG 60W SOUTH OF 16N MOVING WEST NEAR 15 KT. THIS WAVE SPLIT LAST EVENING WITH THE NRN EXTENSION NOW T.S. GORDON. ISOLATED SHOWERS/TSTMS EXIST FROM 10N-14N BETWEEN 56W-63W. A FEW STRONGER CLUSTERS OF MODERATE CONVECTION ARE MOVING W THROUGH NE VENEZUELA. ...THE ITCZ... ITCZ AXIS IS CENTERED ALONG 12N19W 10N31W 9N34W 9N43W 10N46W 10N58W. ASIDE FROM THE WEATHER ASSOCIATED WITH THE TROPICAL WAVES AND SPECIAL FEATURE OFF AFRICA...SCATTERED MODERATE CONVECTION IS FROM 4N-7N BETWEEN 37W-42W. SCATTERED SHOWERS/TSTMS ARE FROM 10N-14N BETWEEN 52W-58W. ...DISCUSSION... THE GULF OF MEXICO... AN UPPER LEVEL HIGH IS OVER CENTRAL MEXICO NEAR 24N102W THAT HAS RIDGING EXTENDING E TO NEAR 26N85W. UPPER DIFFLUENT AIR BETWEEN THE FLOW AROUND THIS HIGH AND THE WESTERLIES OVER THE DEEP SOUTH AND SE US IS HELPING TO SUPPORT THE SCATTERED SHOWERS AND TSTMS SEEN MAINLY IN THE NRN HALF OF THE GULF FROM 25N-30N BETWEEN 83W-97W. GUIDANCE SUGGESTS THE UPPER DIFFLUENCE WILL PERSIST OVER THIS REGION OVER THE NEXT 24HRS...SO THIS SHOULD BE ENOUGH TO KEEP ISOLATED TO SCATTERED SHOWER/TSTMS ACTIVITY CONTINUING. GOES HIGH DENSITY WINDS FROM 250-350MB...ALONG WITH WV IMAGERY...REVEAL AN UPPER ANTICYCLONE OVER THE FLORIDA STRAITS NEAR 24N81W...ALONG WITH AN UPPER TROUGH MOVING W FROM THE YUCATAN. CLUSTERS OF SCATTERED MODERATE CONVECTION ASSOCIATED WITH DIURNAL INFLUENCES OVER CUBA AND THE YUCATAN ARE BEGINNING TO MOVE INTO THE FAR SE GULF AND FAR ERN BAY OF CAMPECHE...RESPECTIVELY. AT THE SURFACE...5-15KT E/SE FLOW IS DOMINATING AROUND THE BASE OF THE SFC HIGH BUILDING S FROM ERN CANADA. THE CARIBBEAN SEA... OVERALL THE CARIBBEAN REMAINS FAIRLY QUIET THIS EVENING...WITH ABUNDANT DRY MID TO UPPER LEVEL AIR ROTATING AROUND THE UPPER HIGH NEAR THE FLORIDA STRAITS. DEBRIS MOISTURE FROM OUR ATLC TROPICAL CYCLONES IS AFFECTING THE NE CARIBBEAN FROM 13N-19N BETWEEN 62W-75W...THOUGH ONLY A FEW ISOLATED SHOWERS/TSTMS ARE SUSPECTED IN THIS REGION. THIS MOISTURE IS GENERALLY MOVING TO THE SW BETWEEN AND UPPER TROUGH NE OF THE LEEWARD ISLANDS AND THE UPPER HIGH OVER THE FL STRAITS. THERE ARE A COUPLE OF SMALL CLUSTERS OF MODERATE CONVECTION AFFECTING THE SW CARIBBEAN FROM 9N-12N BETWEEN 77W-81W...WITH MORE PRONOUNCED ACTIVITY SEEN OVER PANAMA AND NRN COLOMBIA. TRADE WINDS APPEAR TO BE MOSTLY IN THE 10 TO 20 KT RANGE THIS EVENING...EXCEPT LIGHTER FAR NW PORTION. THE ATLANTIC OCEAN.. FLORENCE HAS MOVED OUT OF OUR AREA BUT HAS HELPED TO PUSH A SURGE OF N/NE WINDS AND COOLER/DRIER AIR SOUTHWARD OFF THE EAST COAST...AS THE STORM INTERACTS WITH A STRONG 1033MB HIGH OVER ERN CANADA. SATELLITE IMAGERY AND SFC OBS SUGGESTS A WEAK COLD FRONT MAY BE FORMING IN ASSOCIATION WITH THIS SURGE OF AIR FROM THE NORTH...AND THUS WAS ADDED TO THE 2100 UTC MAP EXTENDING E FROM OFF CNTRL FLORIDA. THIS LARGE FETCH OF NE WINDS WILL CONTINUE TO GENERATE A MODERATE TO STRONG NE SWELL FOR THE SW NORTH ATLANTIC THROUGH MIDWEEK...AND DANGEROUS SURF CONDITIONS FOR BEACHES EXPOSED TO NE SWELL. THIS WILL SLOWLY SUBSIDE THROUGH THE SECOND PART OF THE WEEK...SEE STATEMENTS FROM LOCAL WEATHER SERVICE OFFICES FOR MORE INFO. MOST OF THIS REGION IN THE SW TROPICAL ATLC IS DOMINATED BY DRY MID TO UPPER LEVEL AIR BETWEEN 65W AND THE EAST COAST. AN UPPER TROUGH IS SEEN SPINNING NE OF THE LEEWARD ISLANDS. THIS ALONG WITH DEBRIS MOISTURE FROM FLORENCE IS HELPING TO SUPPORT THE ISOLATED SHOWERS/TSTMS FROM 20N-30N BETWEEN 62W-66W. T.S. GORDON IS JUST E OF THIS AREA AS DESCRIBED ABOVE. A PERSISTENT UPPER LOW IS SEEN SPINNING NEAR 29N38W THAT ONLY HAS A FEW ISOLATED SHOWERS/TSTMS ASSOCIATED WITH IT. AN UPPER HIGH REMAINS OFF THE COAST OF AFRICA AND EXTENDS W TO NEAR 32W. THIS AREA OF THE ERN ATLC OUTSIDE OF THE TROPICAL WAVES AND LOW MOVING OFF AFRICA IS ALSO DOMINATED BY SURFACE HIGH PRESSURE EXTENDING S OF THE AZORES. $$ WILLIS