Show Selection: |
#52076 (Received by flhurricane at: 4:40 PM 16.Oct.2005) TCDAT4 TROPICAL DEPRESSION TWENTY-FOUR DISCUSSION NUMBER 5 NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 5 PM EDT SUN OCT 16 2005 DATA FROM THE AIR FORCE RESERVE RECONNAISSANCE AIRCRAFT INDICATE THAT THE DEPRESSION HAS NOT STRENGTHENED. INDEED...THEY HAVE YET TO FIND ANY FLIGHT-LEVEL WINDS HIGHER THAN 31 KT...WHICH ONLY SUPPORTS 25 KT AT THE SURFACE. IN THE INTEREST OF CONTINUITY HOWEVER...I WILL ASSUME THAT SLIGHTLY HIGHER WINDS EXIST SOMEWHERE THE AIRCRAFT HASN'T YET SAMPLED. WHILE CONDITIONS ALOFT AND AT THE SURFACE ARE VERY FAVORABLE FOR DEVELOPMENT...THE CONVECTIVE PATTERN REMAINS DOMINATED BY OUTER BANDS WITH RELATIVELY LITTLE ACTIVITY NEAR THE CORE. FURTHERMORE...WATER VAPOR IMAGERY INDICATES DRY MID-LEVEL AIR HAS BEEN PUSHING SOUTHWARD TOWARD THE CENTER ALONG THE EASTERN SIDE OF HIGH PRESSURE IN THE GULF OF MEXICO. THESE INHIBITING FACTORS ARE EXPECTED TO BE TEMPORARY...HOWEVER. THE GFDL IS STILL CALLING FOR THE CYCLONE TO REACH MAJOR HURRICANE STATUS IN TWO TO THREE DAYS...WITH THE SHIPS MODEL CALLING FOR MORE GRADUAL DEVELOPMENT. THE INTENSITY FORECAST...SLIGHTLY ABOVE THE SHIPS GUIDANCE...IS UNCHANGED FROM THE PREVIOUS ADVISORY. THE MOTION CONTINUES TO BE SOMEWHAT ERRATIC. EARLIER THE DEPRESSION WAS DRIFTING NORTH-NORTHWESTWARD..BUT NOW THE MOTION APPEARS TO BE WEST-NORTHWESTWARD. A MID-LEVEL SHORT WAVE IS BYPASSING THE NORTHWESTERN BAHAMAS AND THIS SHOULD ALLOW SOME RIDGING TO DEVELOP NORTH OF THE CYCLONE OVER THE NEXT 24 HOURS. CONSEQUENTLY...A TURN BACK TO THE WEST OR WEST-NORTHWEST IS ANTICIPATED. THERE HAS BEEN A SIGNIFICANT WESTWARD SHIFT IN VIRTUALLY ALL OF THE MODEL GUIDANCE...INCLUDING THE LATEST RUNS OF THE GFS...GFDL...UKMET... NOGAPS...AND CANADIAN MODELS...WITH ONLY THE ECMWF RELATIVELY UNMOVED. GENERALLY SPEAKING...THESE MODELS SHOW LESS EROSION OF THE RIDGE IN THE GULF OF MEXICO THAN IN EARLIER RUNS...AND HAVE A MORE ZONAL FLOW ACROSS THE SOUTHERN UNITED STATES IN THE 3 TO 5 DAY TIME FRAME. THE OFFICIAL FORECAST HAS BEEN ADJUSTED WESTWARD...AND IS CLOSE TO THE GFDL...WITH THE UKMET...GFS...AND NOGAPS CONSIDERABLY FARTHER WEST. FORECASTER FRANKLIN FORECAST POSITIONS AND MAX WINDS INITIAL 16/2100Z 17.7N 79.6W 30 KT 12HR VT 17/0600Z 17.8N 79.9W 35 KT 24HR VT 17/1800Z 17.9N 80.4W 45 KT 36HR VT 18/0600Z 18.1N 81.0W 55 KT 48HR VT 18/1800Z 18.4N 81.8W 65 KT 72HR VT 19/1800Z 19.5N 83.5W 80 KT 96HR VT 20/1800Z 21.0N 85.0W 90 KT 120HR VT 21/1800Z 23.5N 86.0W 95 KT |