Direction Interrégionale de LA REUNION
B.P.4    97491 Ste Clotilde Cedex
Téléphone                02.62.92.11.00
Fax exploitation      02.62.92.11.48
Fax direction           02.62.92.11.47

RSMC / TROPICAL CYCLONE CENTRE / LA REUNION TROPICAL CYCLONE FORECAST WARNING (SOUTH-WEST INDIAN OCEAN) 0.A WARNING NUMBER : 18/8/20082009 1.A TROPICAL CYCLONE 8 (GAEL) 2.A POSITION 2009/02/06 AT 0600 UTC : WITHIN 20 NM RADIUS OF POINT 18.4S / 53.1E (EIGHTEEN DECIMAL FOUR DEGREES SOUTH AND FIFTY THREE DECIMAL ONE DEGREES EAST) MOVEMENT : WEST 8 KT 3.A DVORAK ANALYSIS : 5.0/5.0 /D 0.5/6 H 4.A CENTRAL PRESSURE : 955 HPA 5.A MAX AVERAGE WIND SPEED (10 MN) : 75 KT RADIUS OF MAXIMUM WINDS (RMW) : 35 KM 6.A EXTENSION OF WINDS BY QUADRANTS (KM): 30 KT NE: 300 SE: 300 SO: 250 NO: 250 50 KT NE: 050 SE: 070 SO: 070 NO: 050 7.A FIRST CLOSED ISOBARE (PRESSURE / AVERAGE DIAM): 1008 HPA / 900 KM 8.A VERTICAL EXTENSION OF CYCLONE CIRCULATION: DEEP 1.B FORECASTS: 12H: 2009/02/06 18 UTC: 18.8S/51.8E, MAX WIND=090KT, INTENSE TROP. CYCL.. 24H: 2009/02/07 06 UTC: 19.9S/50.9E, MAX WIND=100KT, INTENSE TROP. CYCL.. 36H: 2009/02/07 18 UTC: 20.8S/50.8E, MAX WIND=110KT, INTENSE TROP. CYCL.. 48H: 2009/02/08 06 UTC: 22.2S/51.2E, MAX WIND=100KT, INTENSE TROP. CYCL.. 60H: 2009/02/08 18 UTC: 24.0S/51.9E, MAX WIND=090KT, INTENSE TROP. CYCL.. 72H: 2009/02/09 06 UTC: 26.1S/53.0E, MAX WIND=080KT, TROPICAL CYCLONE. 2.B OTHER INFORMATIONS: T=CI=5.0- GAEL SHOWS AN EYE PATTERN WITH STILL A RAGGED EYE OVER THE LAST EIR IMAGERY. CURRENT INTENSITY IS BASED ON AN AVERAGE OF DVORAK ANALYSIS IN EIR IMAGERY OVER THE LAST 6 HOURS. MOTION AND SPEED OVER THE LAST 6 HOURS IS ESTIMATED AT : 270/8KT ENVIRONMENT HAS BECOME FAVOURABLE AS THE WINDSHEAR HAS DECREASED AND DUE TO THE PRESENCE OF AN EXCELLENT EQUATORWARD OUTFLOW. POLEWARD UPPER LEVEL DIVERGENCE IS LIMITED. GAEL TRACKS UNDER THE STEERING FLOW OF A MID TO UPPER LEVEL RIDGE PRESENT IN THE SOUTH OF THE SYSTEM, WHICH SHOULD THEREFORE KEEP ON TRACKING WESTSOUTHWESTWARD FOR THE NEXT 12 HOURS. BEYOND, A WEAKNESS IN THE MID TO HIGH LEVEL RIDGE (DUE TO A MID LAT TROUGH) SHOULD RECURVE THE TRACK SOUTHWESTWARDS, AND THEN SOUTHWARDS. ENVIRONMENTAL CONDITIONS SHOULD KEEP ON IMPROVING: BETTER TRADES INFLOW, HIGH SST, PRESENCE OF A POLEWARD OUTFLOW DUE TO THE TROUGH. CURRENT FORECAST TRACK IS CLOSE TO A CONSENSUS OF THE AVAILABLE NWP MODELS EXCEPT NOGAPS AND GFDN THAT APPEAR TOO MUCH EASTWARDS SINCE A LONG TIME. AT THE END OF THE FORECAST PERIOD, COOLER SST SHOULD INDUCE A WEAKENING TREND.