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 : 9/11/20082009 1.A SEVERE TROPICAL STORM 11 (IZILDA) 2.A POSITION 2009/03/26 AT 0600 UTC : 23.8S / 42.6E (TWENTY THREE DECIMAL EIGHT DEGREES SOUTH AND FORTY TWO DECIMAL SIX DEGREES EAST) MOVEMENT : QUASI-STATIONARY 3.A DVORAK ANALYSIS : 3.0/3.5 /W 1.0/6 H 4.A CENTRAL PRESSURE : 985 HPA 5.A MAX AVERAGE WIND SPEED (10 MN) : 50 KT RADIUS OF MAXIMUM WINDS (RMW) : 30 KM 6.A EXTENSION OF WINDS BY QUADRANTS (KM): 30 KT NE: 050 SE: 200 SO: 200 NO: 050 50 KT NE: 020 SE: 020 SO: 020 NO: 020 7.A FIRST CLOSED ISOBARE (PRESSURE / AVERAGE DIAM): 1008 HPA / 600 KM 8.A VERTICAL EXTENSION OF CYCLONE CIRCULATION: DEEP 1.B FORECASTS: 12H: 2009/03/26 18 UTC: 23.8S/42.2E, MAX WIND=040KT, MODERATE TROP. STORM. 24H: 2009/03/27 06 UTC: 23.4S/41.3E, MAX WIND=040KT, MODERATE TROP. STORM. 36H: 2009/03/27 18 UTC: 23.0S/40.5E, MAX WIND=035KT, MODERATE TROP. STORM. 48H: 2009/03/28 06 UTC: 22.8S/39.6E, MAX WIND=030KT, TROP. DEPRESSION. 60H: 2009/03/28 18 UTC: 22.8S/38.5E, MAX WIND=030KT, TROP. DEPRESSION. 72H: 2009/03/29 06 UTC: 22.9S/37.1E, MAX WIND=030KT, TROP. DEPRESSION. 2.B OTHER INFORMATIONS: T=3.0- CI=3.5 INERTIA BETWEEN SYSTEM PATTERN AND TRUE WEAKENING IS LESS FOR SMALL SIZES SYSTEMS (6H). NORTHWESTERLY VERTICAL WINDSHEAR IS OBVIOUS ON THE IMAGERY. LLCC IS PARTIALLY EXPOSED WEST OF THE CONVECTION, WHICH IS EASTWARDS AWAY OVER THE SOUTHWESTERN PART OF MADAGASCAR. MICROWAVE (AMSU 0226Z) AND WATER VAPOR IMAGERIES SHOW A DRIER AIR INTRUSION IN THE WEST. IZILDA HAS TRACKED ERRATICALLY BUT SHOULD TRACK WESTWARDS FOR THE NEXT HOURS, UNDER THE STEERING INFLUENCE OF THE SUBTROPICAL HIGH PRESSURES. UPPER-LEVEL JET PRESENT IN THE SOUTHWEST OF THE SYSTEM IS EXPECTED TO BE A LIMITATING FACTOR. THEN THE STRENGTHENING NORTHERLY WINDSHEAR (BEYOND TAU36) SHOULD WEAKEN THIS SMALL SIZE SYSTEM.