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#29833 (Received by flhurricane at: 10:56 PM 03.Jul.2005) TCDAT3 TROPICAL DEPRESSION THREE DISCUSSION NUMBER 2 NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 11 PM EDT SUN JUL 03 2005 DURING THE PAST 6 HOURS...A STRONG CONVECTIVE BURST HAS DEVELOPED OVER THE LOW-LEVEL CENTER INDICATED BY THE LAST RECON REPORT... WHICH ALSO INDICATED A CENTRAL PRESSURE OF 1007 MB -- A DROP OF 2 MB IN 2.5 HOURS. RADAR REPORTS FROM THE RECON AIRCRAFT ALSO INDICATED SIGNIFICANT BANDING HAD DEVELOPED TO THE EAST AND NORTH OF THE CENTER. GIVEN THE SHARP INCREASE IN THE CENTRAL DEEP CONVECTION... THE CYCLONE COULD EASILY BE AT TROPICAL STORM STRENGTH. THE INTENSITY WILL BE MAINTAINED AT 30 KT...DESPITE SATELLITE INTENSITY ESTIMATES OF ONLY 25 KT..MAINLY TO SEE IF THE CURRENT CONVECTIVE TREND CONTINUES FOR ANOTHER 3 TO 6 HOURS. INITIAL MOTION ESTIMATE IS 305/08. THE DEPRESSION HAS MADE A SLIGHT JOG TO THE RIGHT...WHICH MAY BE DUE TO REDEVELOPMENT CLOSER TO THE DEEP CONVECTION AND/OR SOME WEAK BINARY INTERACTION WITH A MID- TO UPPER-LEVEL CIRCULATION LOCATED TO THE NORTH OVER THE YUCATAN CHANNEL. ALL OF THE GLOBAL MODEL AGREE THAT THE LATTER FEATURE IS NOT EXPECTED TO BE A SIGNIFICANT STEERING FACTOR AS IT WEAKENS AND LIFTS OUT TO THE NORTH-NORTHWEST. ALL OF THE GLOBAL MODELS AND THE GFDL ALSO AGREE THAT THE SUBTROPICAL RIDGE LYING EAST-WEST ALONG 28N LATITUDE FROM FLORIDA ACROSS THE NORTHERN GULF OF MEXICO WILL REMAIN IN PLACE THROUGH THE PERIOD. A VIGOROUS SHORTWAVE TROUGH CURRENTLY OVER ARKANSAS AND LOUISIANA IS EXPECTED TO MOVE QUICKLY EASTWARD...BUT IN ITS WAKE LEAVE A WEAKNESS IN THE RIDGE AXIS OVER THE NORTHWESTERN GULF ALONG 94-95W LONGITUDE. THIS IS EXPECTED TO BE THE PATH OF LEAST RESISTANCE FOR THE CYCLONE TO TAKE UNTIL IT NEARS THE TEXAS-LOUISIANA COAST AND IS TURNED SHARPLY NORTHEAST OR EVEN EASTWARD AS THE SYSTEM ENCOUNTERS MODERATE UPPER-LEVEL WESTERLIES. THE OFFICIAL TRACK IS A LITTLE TO THE RIGHT OF THE PREVIOUS TRACK...AND TO THE LEFT OF THE 18Z GFDL MODEL RUN. LITTLE CHANGE IN INTENSITY IS EXPECTED WHILE THE CYCLONE IS OVER THE YUCATAN THROUGH 24 HOURS. AFTER THAT...THE COMBINATION OF WEAK VERTICAL SHEAR OF LESS THAN 8 KT AND WARM SSTS NEAR 29C SHOULD ALLOW FOR AT LEAST MODERATE INTENSIFICATION. THE UPPER-LEVEL FLOW PATTERN ACTUALLY FAVORS MORE SIGNIFICANT STRENGTHENING AS INDICATED BY THE SHIPS MODEL...WHICH BRINGS THE CYCLONE TO HURRICANE STRENGTH BY 72 HOURS. HOWEVER...THERE IS ONE POSSIBLE INHIBITING FACTOR... WHICH IS DRY MID-LEVEL AIR OF 30-40 PERCENT HUMIDITY POSSIBLY GETTING GETTING ENTRAINED INTO THE SYSTEM FROM THE WEST AFTER 36-48 HOURS. THE INTENSITY FORECAST REMAINS SIMILAR TO THE PREVIOUS FORECAST AND SLIGHTLY LESS THAN THE SHIPS MODEL. FORECASTER STEWART FORECAST POSITIONS AND MAX WINDS INITIAL 04/0300Z 18.9N 87.5W 30 KT 12HR VT 04/1200Z 19.7N 88.6W 30 KT...INLAND 24HR VT 05/0000Z 21.1N 90.1W 30 KT...INLAND 36HR VT 05/1200Z 22.9N 91.8W 40 KT 48HR VT 06/0000Z 25.0N 93.3W 45 KT 72HR VT 07/0000Z 28.5N 94.5W 55 KT 96HR VT 08/0000Z 31.0N 93.5W 35 KT...INLAND 120HR VT 09/0000Z 33.0N 91.0W 25 KT...DISSIPATING INLAND |