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 : 6/11/20082009 1.A MODERATE TROPICAL STORM 11 (IZILDA) 2.A POSITION 2009/03/25 AT 1200 UTC : WITHIN 20 NM RADIUS OF POINT 23.6S / 42.2E (TWENTY THREE DECIMAL SIX DEGREES SOUTH AND FORTY TWO DECIMAL TWO DEGREES EAST) MOVEMENT : SOUTH-SOUTH-EAST 5 KT 3.A DVORAK ANALYSIS : 3.5/3.5 /D 1.0/24 H 4.A CENTRAL PRESSURE : 988 HPA 5.A MAX AVERAGE WIND SPEED (10 MN) : 45 KT RADIUS OF MAXIMUM WINDS (RMW) : 30 KM 6.A EXTENSION OF WINDS BY QUADRANTS (KM): 30 KT NE: 230 SE: 130 SO: 340 NO: 230 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 00 UTC: 23.8S/42.4E, MAX WIND=060KT, SEVERE TROP. STORM. 24H: 2009/03/26 12 UTC: 23.6S/42.6E, MAX WIND=065KT, TROPICAL CYCLONE. 36H: 2009/03/27 00 UTC: 23.2S/41.8E, MAX WIND=060KT, SEVERE TROP. STORM. 48H: 2009/03/27 12 UTC: 22.9S/41.1E, MAX WIND=050KT, SEVERE TROP. STORM. 60H: 2009/03/28 00 UTC: 22.7S/40.3E, MAX WIND=040KT, MODERATE TROP. STORM. 72H: 2009/03/28 12 UTC: 22.5S/38.9E, MAX WIND=030KT, TROP. DEPRESSION. 2.B OTHER INFORMATIONS: T=CI=3.5- SATELLITE PRESENTATION (ENFORCED INFRARED AND VISIBLE CHANNEL) HAS CLEARLY IMPROVED SINCE 0300Z, AND SHOWS SINCE 0600Z A CURVED BAND PATTERN WRAPPING OF 7 TO 8 TENS AROUND THE CENTER. LOW LEVEL CONFIGURATION REMAINS CLEARLY DEFINED (CF MICROWAVE IMAGERY 37GHZ SSMIS-F16 AT 0455Z AND F17 AT 0222Z). SYSTEM KEEPS ON TRACKING SLOWLY SOUTH-SOUTHEASTWARDS UNDER THE STEERING INFLUENCE OF THE MID-LEVEL RIDGE EXISTING IN ITS NORTHEAST THEN BECOMING STATIONNARY WITHIN THE NEXT 24 HOURS DUE TO TWO OPPOSITE STEERING FLOWS IN RELATIONSHIP WITH THE REBUILDING MID-LEVEL RIDGE IN THE SOUTHWEST. THIS SUBTROPICAL RIDGE IS EXPECTED TO BECOME THE MAIN STEERING FLOW BEYOND TAU36, SYSTEM IS ALSO EXPECTED TO RECURVE WEST-NORTHWESTWARDS. UPPER-LEVEL JET (WELL SHOWED ON INFRARED METEOSAT7 IMAGERY) EXISTING IN THE WEST AND IN THE SOUTH OF THE SYSTEM IS EXPECTED TO KEEP ON IMPROVING THE UPPER LEVEL POLEWARD DIVERGENCE BUT COULD BECOME A LIMITATING FACTOR AS THE SYSTEM RECURVE WEST-NORTHWESTWARDS (BEYOND TAU36) LINKED TO A STRENGTHENING WINDSHEAR. IZILDA COULD BEFORE REACH THE MINIMAL TROPICAL CYCLONE STAGE.