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
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RSMC / TROPICAL CYCLONE CENTRE / LA REUNION TROPICAL CYCLONE FORECAST WARNING (SOUTH-WEST INDIAN OCEAN) 0.A WARNING NUMBER : 12/12/20082009 1.A OVERLAND DEPRESSION 12 (EX-JADE) 2.A POSITION 2009/04/07 AT 0000 UTC : WITHIN 20 NM RADIUS OF POINT 18.5S / 48.6E (EIGHTEEN DECIMAL FIVE DEGREES SOUTH AND FORTY EIGHT DECIMAL SIX DEGREES EAST) MOVEMENT : SOUTH-SOUTH-WEST 11 KT 3.A DVORAK ANALYSIS : / 4.A CENTRAL PRESSURE : 5.A MAX AVERAGE WIND SPEED (10 MN) : 30 KT RADIUS OF MAXIMUM WINDS (RMW) : NIL 6.A EXTENSION OF WINDS BY QUADRANTS (KM): 30 KT NE: 250 SE: 250 SO: NO: 7.A FIRST CLOSED ISOBARE (PRESSURE / AVERAGE DIAM): 1009 HPA / 900 KM 8.A VERTICAL EXTENSION OF CYCLONE CIRCULATION: MEDIUM 1.B FORECASTS: 12H: 2009/04/07 12 UTC: 20.4S/48.1E, MAX WIND=030KT, OVERLAND. 24H: 2009/04/08 00 UTC: 21.6S/47.8E, MAX WIND=020KT, OVERLAND. 36H: 2009/04/08 12 UTC: 22.3S/47.4E, MAX WIND=020KT, DISSIPATING. 48H: 2009/04/09 00 UTC: 22.7S/47.3E, MAX WIND=015KT, DISSIPATING. 60H: 2009/04/09 12 UTC: 23.5S/47.5E, MAX WIND=015KT, DISSIPATING. 72H: 2009/04/10 00 UTC: 24.1S/47.4E, MAX WIND=015KT, DISSIPATED. 2.B OTHER INFORMATIONS: THE SYSTEM TRACKS SOUTHWARD UNDER THE STEERING INFLUENCE OF THE MID LAVEL SUBTROPICAL RIDGE LOCATED IN THE EAST. 12Z RUN SHOW A LESS SPREAD THAN THE 00Z RUN FOR THE TRACK FORECASTS. NGP STILL TRACKS THE SYSTEM ON WEDNESDAY NIGHT OFF THE SOUTHWESTERN COAST OF MADAGASCAR, BUT OTHER AVAILABLE MODELS ARE IN GOOD AGREEMENT WITH A SOUTHWARDS TRACK OVERLAND, ALONG THE EASTERN MALAGASY COAST. ECMWF/UKMO TRACK THE SYSTEM BACK OVER WATER OFF THE EASTERN MALAGASY COAST AT THE END OF THE WEEK. BEYOND RANGE 36H, THE SYSTEM SHOULD STRONGLY SLOW DOWN DUE TO THE NEW SUBTROPICAL RIDGE. PRESENT FORECAST IS BASED ON A GLOBAL CONSENSUS OF ALL AVAILABLE NWP MODELS. ACCORDING TO THIS SCENARIO, THE SYSTEM STAYS OVERLAND AND COULD DISSIPATE WITHIN THE FORECAST PERIOD. HOWEVER IT IS IMPORTANT TO NOTICE THAT THERE IS A STRONGER THAN USUAL UNCERTAINTY ASSOCIATED WITH THE FORECAST TRACK. IT IS NOT UNLIKELY THAT THE SYSTEM COULD MOVE BACK OVER WATER WITHIN THE NEXT 72 HOURS OFF THE EASTERN COAST OF MADAGASCAR.