Show Selection: |
#624299 (Received by flhurricane at: 10:41 PM 14.Aug.2013) TCDAT5 TROPICAL DEPRESSION FIVE DISCUSSION NUMBER 1 NWS NATIONAL HURRICANE CENTER MIAMI FL AL052013 1100 PM AST WED AUG 14 2013 ASCAT DATA FROM EARLIER THIS EVENING INDICATED THAT THE AREA OF LOW PRESSURE NEAR THE CAPE VERDE ISLANDS HAS AN INNER CORE REGION OF LIGHT WINDS SURROUNDED BY A BAND OF STRONGER WINDS NEAR 30 KT...BUT THE CENTER APPEARS SUFFICIENTLY WELL DEFINED TO FIT THE DEFINITION OF A TROPICAL CYCLONE. DVORAK INTENSITY ESTIMATES WERE ONLY T1.0 FROM TAFB AND SAB AT 0000 UTC...BUT GIVEN RECENT CONVECTIVE TRENDS AND THE OVERALL STRUCTURE...ADVISORIES ARE BEING INITIATED ON TROPICAL DEPRESSION FIVE. THE DEPRESSION IS CURRENTLY IN AN ENVIRONMENT THAT IS CONDUCIVE FOR STRENGTHENING...CHARACTERIZED BY LOW WIND SHEAR...WARM SSTS...AND A MOIST AIR MASS. THIS ENVIRONMENT...HOWEVER...WILL BECOME A LITTLE LESS FAVORABLE IN A FEW DAYS WHEN THE CYCLONE IS EXPECTED TO REACH SLIGHTLY COOLER SSTS AND A MORE STABLE ENVIRONMENT. IN ADDITION... THE DEPRESSION IS LIKELY TO BE CUT OFF FROM ITS DEEP MOISTURE SOURCE TO THE SOUTH IN ABOUT 3 DAYS. THEREFORE...MODEST STRENGTHENING IS INDICATED IN THE OFFICIAL FORECAST THROUGH THE FIRST 48 HOURS WITH SOME WEAKENING BY THE END OF THE FORECAST PERIOD. THIS FORECAST IS VERY NEAR THE INTENSITY CONSENSUS. THE DEPRESSION IS LOCATED ON THE SOUTHERN PERIPHERY OF A NARROW MID-LEVEL RIDGE...AND IT HAS AN INITIAL MOTION OF 290/12 KT. THE RIDGE IS EXPECTED TO BE RATHER WEAK FOR THE NEXT FEW DAYS DUE TO A CLOSED MID- TO UPPER-LEVEL LOW LOCATED SOUTH OF THE AZORES...AND THIS PATTERN SHOULD KEEP THE CYCLONE ON A WEST-NORTHWESTWARD TRAJECTORY THROUGH THE FIRST 3 DAYS. ONCE WEAKENING BEGINS IN 4 TO 5 DAYS...LOWER-LEVEL FLOW WILL TAKE OVER AND SHOULD STEER THE SYSTEM ON A MORE WESTERLY TRACK. WITH THE EXCEPTION OF THE GFDL MODEL...WHICH SHOWS A SLOWER AND MORE NORTHERLY SOLUTION...THE OTHER TRACK MODELS ARE IN DECENT AGREEMENT THROUGH 5 DAYS. THE NHC TRACK FORECAST IS THEREFORE VERY CLOSE TO THE MODEL CONSENSUS TVCA. FORECAST POSITIONS AND MAX WINDS INIT 15/0300Z 14.0N 23.5W 30 KT 35 MPH 12H 15/1200Z 14.5N 25.2W 35 KT 40 MPH 24H 16/0000Z 15.1N 27.9W 40 KT 45 MPH 36H 16/1200Z 15.7N 30.6W 45 KT 50 MPH 48H 17/0000Z 16.5N 32.9W 50 KT 60 MPH 72H 18/0000Z 17.5N 37.0W 50 KT 60 MPH 96H 19/0000Z 17.5N 41.5W 45 KT 50 MPH 120H 20/0000Z 17.5N 46.0W 40 KT 45 MPH $$ FORECASTER BERG/STEWART |