000 AXNT20 KNHC 301759 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 205 PM EDT TUE OCT 30 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 1715 UTC. ...SPECIAL FEATURE... TROPICAL STORM NOEL IS CENTERED NEAR 21.0N 77.7W AT 30/1800 UTC...OR ABOUT 25 NM S-SE OF CAMAGUEY CUBA AND ABOUT 240 NM S OF NASSAU IN THE NW BAHAMAS...MOVING W NEAR 7 KT. ESTIMATED MINIMUM CENTRAL PRESSURE IS 1002 MB. MAXIMUM SUSTAINED WINDS ARE NOW NEAR 35 KT WITH GUSTS TO 45 KT. LITTLE CHANGE IN STRENGTH IS FORECAST DURING THE NEXT 24 HOURS AS NOEL REMAINS INLAND OVER CUBA THROUGH TONIGHT...BEFORE EMERGING OFF THE NORTHERN COAST OF CUBA BY TOMORROW. SEE THE NHC FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMAT1/WTNT21 KNHC AND/OR THE PUBLIC ADVISORY UNDER MIATCPAT1/WTNT31 KNHC FOR MORE DETAILS. SATELLITE IMAGERY...SURFACE OBSERVATIONS AND RADAR FROM CAMAGUEY CUBA INDICATE THAT CENTER OF NOEL REMAINS INLAND OVER EASTERN CUBA. HOWEVER...RAINBANDS CONTINUE TO EXTEND WELL AWAY FROM THE CENTER AND ARE SPREADING INTO THE BAHAMAS. NOEL IS EXPECTED TO PRODUCE SIGNIFICANT RAINFALL ACCUMULATIONS OVER HISPANIOLA...SOUTHEASTERN CUBA... AND THE BAHAMAS. THESE RAINS...PARTICULARLY IN HISPANIOLA... ARE EXPECTED TO CAUSE LIFE-THREATENING FLASH FLOODS AND MUD SLIDES. IN ADDITION TO THE RAINFALL THREAT...THE INTERACTION BETWEEN NOEL...STRONG HIGH PRESSURE OVER THE VIRGINIAS...AND A STATIONARY FRONT EXTENDING ENE FROM CENTRAL FLORIDA IS PRODUCING STRONG GUSTY ENE WINDS OVER PORTIONS OF FLORIDA AND THE ADJACENT WATERS. THIS HAS ALLOWED SEAS TO BUILD INTO THE 10-15 FT RANGE IN THE AREA OFFSHORE FLORIDA AND THE BAHAMAS. THESE SEAS ARE EXPECTED TO BUILD FURTHER THROUGH MIDWEEK AS NOEL MOVES NW INTO THE AREA...SEE HIGH SEAS FORECASTS UNDER AWIPS HEADER NFDHSFAT1 AND STATEMENTS FROM LOCAL WEATHER OFFICES FOR MORE DETAILS. ...TROPICAL WAVES... TROPICAL WAVE PREVIOUSLY ALONG 63W HAS BEEN ADJUSTED SLIGHTLY TO THE W TO 66W ON THE 30/1200 UTC MAP...BASED ON THE SURGE OF MOISTURE NOTED MOVING THROUGH THE AREA IN THE UW-CIMSS TPW PRODUCT OVER THE LAST COUPLE OF DAYS...VISIBLE IMAGERY...AND 850 MB SATELLITE DERIVED VORTICITY. HOWEVER...THE WAVE MAY EVENTUALLY NEED TO BE DROPPED SOMETIME OVER THE NEXT DAY OR SO AS THE ASSOCIATED MOISTURE/ENERGY MOVES NW WITH SE FLOW AHEAD OF T.S. NOEL...AND POSSIBLY GETS ABSORBED BY THE TROPICAL CYCLONE. THE WAVE ITSELF ONLY APPEARS TO BE GENERATING ISOLATED SHOWERS/TSTMS WITHIN 90 NM OF THE AXIS. ...THE ITCZ... THE ITCZ AXIS IS CENTERED ALONG 8N13W 8N30W 5N45W 3N52W. A FAIRLY LARGE AREA OF ACTIVE WEATHER IS NEAR THE ITCZ BETWEEN 20W-45W. SPECIFICALLY...NUMEROUS MODERATE WITH EMBEDDED AREAS OF STRONG CONVECTION ARE WITHIN 150NM N AND 90NM S OF THE AXIS BETWEEN 21W-44W. IT IS PROBABLE THAT AT LEAST ONE LOW AMPLITUDE TROPICAL WAVE IS EMBEDDED IN THIS REGION. THE DAKAR RAOB DATA SHOWED A CLEAR WAVE PASSAGE AROUND 12Z ON OCTOBER 27...WITH THE SAL SOUNDING DATA SHOWING A SIMILAR PASSAGE ABOUT A DAY LATER. BASED SOLELY ON FORWARD EXTRAPOLATION...THIS WOULD MEAN THAT A LOW AMPLITUDE TROPICAL WAVE IS SOMEWHERE IN THE VICINITY OF 33W. THIS ALSO COINCIDES TO WHERE THE MOST POLEWARD INFLECTION OF THE ITCZ IS. THERE APPEARS TO BE SOME SUBTLE LOW LEVEL CYCLONIC TURNING IN THIS REGION...BUT THE FEATURE IS NOT WELL-DEFINED. GIVEN THE RATHER POOR SATELLITE APPEARANCE AT THE MOMENT...AND THE FACT THAT THE WAVE WILL UNDOUBTEDLY BE DIFFICULT TO TRACK...HAVE OPTED TO LEAVE THE FEATURE OFF AT THE MOMENT. WILL REVISIT THIS ON FUTURE MAPS. DISCUSSION... GULF OF MEXICO... A STATIONARY FRONT EXTENDS FROM CENTRAL FLORIDA W ACROSS THE MIDDLE GULF AND THEN SSW TO THE CENTRAL BAY OF CAMPECHE...GENERALLY ALONG 28N82W 26N92W 18N93W. ISOLATED SHOWERS AND TSTMS ARE MAINLY WITHIN 120 NM AHEAD OF THE WRN PORTION OF THE FRONT N OF THE YUCATAN. THE FRONT REMAINS EVIDENT IN SATELLITE IMAGERY AS A RAGGED LINE OF BROKEN LOW TO MID CLOUDS. ASIDE FROM THAT THOUGH...THE FRONT IS NOT CLASSIC WITH NE WINDS ON BOTH SIDES OF THE BOUNDARY. A DEWPOINT GRADIENT REMAINS EVIDENT HOWEVER...WITH THE 70 DEGREE ISODROSOTHERM THE MAIN PARAMETER USED IN THE FRONTAL PLACEMENT. REGARDLESS...THE GULF PORTION OF THE FRONT IS EXPECTED TO CONTINUE BECOMING DIFFUSE OVER THE NEXT DAY OR SO. ELSEWHERE AT THE SFC...STRONG HIGH PRES CENTERED OVER VIRGINIA IS INTERACTING WITH THE FRONT AND THE GRADIENT AROUND T.S. NOEL OVER CUBA TO PRODUCE FRESH TO STRONG NE WINDS OVER MUCH OF THE BASIN. A GALE WARNING REMAINS IN EFFECT FOR THE FAR SW GULF BUT IS EXPECTED TO BE ALLOWED TO EXPIRE BY TONIGHT. ALOFT...FLOW IS FAIRLY UNIFORM SW AHEAD OF A SHORTWAVE TROUGH NEARING THE COAST OF TEXAS. CARIBBEAN SEA... TROPICAL STORM NOEL REMAINS INLAND OVER CUBA...SEE SPECIAL FEATURE SECTION. TROUGHING S OF THE TROPICAL CYCLONE DOMINATES MUCH OF THE WRN CARIBBEAN. LOW LEVEL S/SW FLOW BETWEEN THE COAST OF COLOMBIA AND ERN CUBA IS CONVERGING WITH MORE OF A MODERATE E TO SE FLOW IN THE EASTERN CARIBBEAN...PRODUCING NUMEROUS SHOWERS WITH EMBEDDED TSTMS BETWEEN 71W-78W. THIS ACTIVITY MAY ALSO BE GETTING SOME SUPPORT BY AN UPPER COL REGION BETWEEN ANTICYCLONES OVER THE E AND W PORTIONS OF THE BASIN. SCATTERED SHOWERS/ISOLATED TSTMS ARE ALSO OVER THE SW CARIBBEAN S OF 14N...AND JUST OFF THE S COAST OF BELIZE S OF 18N W OF 87W. ELSEWHERE...DEEP CONVECTION IS MINIMAL. TRADE FLOW IS EXPECTED TO REMAIN DISRUPTED OVER THE WRN CARIBBEAN OVER THE NEXT COUPLE OF DAYS DUE TO THE TROUGHING S OF T.S. NOEL. LIGHT TO MODERATE TRADES ARE ANTICIPATED OVER THE ERN CARIBBEAN. ATLANTIC OCEAN... THE MAIN STORY CONTINUES TO BE TROPICAL STORM NOEL OVER CUBA. NOEL IS INTERACTING WITH STRONG HIGH PRES OVER THE MID ATLC STATES AND A STATIONARY FRONT EXTENDING ENE FROM CENTRAL FLORIDA...WHICH IS PRODUCING STRONG GUSTY WINDS AND LARGE SEAS OVER MUCH OF THE WRN ATLC. SEE DETAILS ABOVE IN SPECIAL FEATURE SECTION. NUMEROUS SHOWERS/SCATTERED TSTMS ASSOCIATED WITH NOEL ARE MAINLY S OF 26N BETWEEN 66W-78W. UPPER DIFFLUENCE IS ALSO ENHANCING THIS ACTIVITY...BETWEEN AN UPPER LOW JUST N OF ERN CUBA...AND RIDGING EXTENDING N INTO THE ATLC FROM THE ERN CARIBBEAN. A WEAK SFC TROUGH IS OVER THE CENTRAL ATLC ALONG 32N53W 24N59W. WHILE WINDS ARE FAIRLY LIGHT IN THE VICINITY OF THIS TROUGH...THERE IS A CLEAR CYCLONIC SHIFT IN WIND DIRECTION AROUND THE BOUNDARY. HOWEVER...THE FEATURE ONLY APPEARS TO BE GENERATING ISOLATED SHOWER ACTIVITY WITHIN 30NM OF THE AXIS. AN UPPER LOW NEAR 19N52W IS GENERATING HIGH CLOUDS AND POSSIBLE ISOLATED SHOWERS FROM 15N-23N BETWEEN 43W-50W. THE REMAINDER OF THE E ATLC IS MOSTLY QUIET WITH TYPICAL PATCHES OF STABLE STRATOCUMULUS CLOUDS. TRADES ARE MOSTLY MODERATE OVER THE AREA S OF 25N E OF 65W...WITH SLIGHTLY STRONGER NE WINDS NOTED JUST OFF THE COAST OF NW AFRICA IN THE VICINITY OF THE CANARY ISLANDS. A BROAD UPPER TROUGH IS OVER THE NE PORTION OF THE AREA...BUT DOES NOT APPEAR TO BE GENERATING SIGNIFICANT WEATHER. $$ WILLIS