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 : 34/11/20072008 1.A TROPICAL CYCLONE 11 (IVAN) 2.A POSITION 2008/02/15 AT 1200 UTC : WITHIN 20 NM RADIUS OF POINT 15.6S / 54.7E (FIFTEEN DECIMAL SIX DEGREES SOUTH AND FIFTY FOUR DECIMAL SEVEN DEGREES EAST) 3.A DVORAK ANALYSIS : 4.5/4.5 /D 1.0/24 H 4.A CENTRAL PRESSURE : 970 HPA 5.A MAX AVERAGE WIND SPEED (10 MN) : 65 KT 6.A EXTENSION OF WINDS BY QUADRANTS (KM): 30 KT NE: 300 SE: 280 SO: 240 NO: 300 50 KT NE: 070 SE: 070 SO: 070 NO: 070 7.A FIRST CLOSED ISOBARE (PRESSURE / AVERAGE DIAM): 1006 HPA / 1000 KM 8.A VERTICAL EXTENSION OF CYCLONE CIRCULATION: DEEP 1.B FORECASTS: 12H: 2008/02/16 00 UTC: 16.0S/53.3E, MAX WIND=075KT, TROPICAL CYCLONE. 24H: 2008/02/16 12 UTC: 16.8S/51.8E, MAX WIND=080KT, TROPICAL CYCLONE. 36H: 2008/02/17 00 UTC: 17.4S/50.8E, MAX WIND=090KT, INTENSE TROP. CYCL.. 48H: 2008/02/17 12 UTC: 18.0S/49.4E, MAX WIND=095KT, INTENSE TROP. CYCL.. 60H: 2008/02/18 00 UTC: 18.3S/48.1E, MAX WIND=050KT, OVERLAND. 72H: 2008/02/18 12 UTC: 19.4S/47.4E, MAX WIND=030KT, OVERLAND. 2.B OTHER INFORMATIONS: T=4.5- AND CI=4.5- IVAN KEEPS ON TRACKING WEST-SOUTHWESTWARDS AT 10 KT WITHIN THE PAST 6 HOURS. LOW LEVEL CIRCULATION CENTER IS EXPECTED TO TRACK CLOSE TO THE NORTH OF TROMELIN'S ISLAND WITHIN THE NEXT FEW HOURS. AT 1200Z, AT TROMELIN MSLP IS 979.6 HPA WITH 10MN WINDS UP TO 51 KT AND GUSTS UP TO 72 KT. 0000Z NWP MODEL RUNS ARE IN VERY GOOD AGREEMENT FOR A WEST-SOUTHWESTWARDS TRACK WITHIN THE NEXT 48 HOURS. SUBTROPICAL RIDGE APPEARS NOW TO HOLD THE SYSTEM ON A GENERALLY WESTSOUTHWARDS TRACK ALONG THE NORTHERN EDGE OF THE SUBTROPICAL RIDGE. IT SHOULD KEEP ON REGULARY INTENSIFYING WITHIN A FAVORABLE ENVIRONMENT (HIGH OCEAN HEAT CONTAIN AND DECREASING SHEAR). SPREAD ON THE ECMWF ENSEMBLE FORECAST SYSTEM HAS REDUCED AGAIN SENSITIVELY ON THE LAST RUN... GIVEN SOME CONFIDENCE ON THE GUIDANCE. SO THIS FORECAST IS CLOSE TO THE ECMWF AND ITS ENSEMBLE PREDICTION SYSTEM SOLUTIONS. IVAN IS NOW A SERIOUS THREAT FOR THE CENTRAL EAST COAST OF MADAGASCAR. WINDS EXTENSION HAS BEEN RECALIBRATED THANKS TO 0511Z ASCAT SWATH.