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 : 13/4/20072008 1.A TROPICAL DEPRESSION 4 (0420072008) 2.A POSITION 2007/12/15 AT 1200 UTC : 15.6S / 67.4E (FIFTEEN DECIMAL SIX DEGREES SOUTH AND SIXTY SEVEN DECIMAL FOUR DEGREES EAST) 3.A DVORAK ANALYSIS : 2.5/2.5 /S 0.0/12 H 4.A CENTRAL PRESSURE : 999 HPA 5.A MAX AVERAGE WIND SPEED (10 MN) : 30 KT 6.A EXTENSION OF WINDS BY QUADRANTS (KM): 30 KT NE: 130 SE: 370 SO: 280 NO: 150 7.A FIRST CLOSED ISOBARE (PRESSURE / AVERAGE DIAM): 1005 HPA / 1006 KM 8.A VERTICAL EXTENSION OF CYCLONE CIRCULATION: MEDIUM 1.B FORECASTS: 12H: 2007/12/16 00 UTC: 16.3S/66.2E, MAX WIND=030KT, TROP. DEPRESSION. 24H: 2007/12/16 12 UTC: 17.1S/64.8E, MAX WIND=035KT, MODERATE TROP. STORM. 36H: 2007/12/17 00 UTC: 18.0S/63.4E, MAX WIND=040KT, MODERATE TROP. STORM. 48H: 2007/12/17 12 UTC: 18.8S/62.0E, MAX WIND=040KT, MODERATE TROP. STORM. 60H: 2007/12/18 00 UTC: 19.4S/60.8E, MAX WIND=040KT, MODERATE TROP. STORM. 72H: 2007/12/18 12 UTC: 20.0S/59.4E, MAX WIND=040KT, MODERATE TROP. STORM. 2.B OTHER INFORMATIONS: T=CI=2.5- THE LOW LEVEL CLOCKWISE CIRCULATION IS EXPOSED IN THE NORTHEAST OF THE DEEP CONVECTION THAT IS SOUTHWESTWARDS AWAY FROM THE CENTER, DUE TO THE PERSISTING RATHER STRONG NORTHEASTERLY VERTICAL WINDSHEAR. ENVIRONMENTAL CONDITIONS REMAIN POORLY FAVORABLE FOR INTENSIFICATION, DUE TO THE VERTICAL WINDSHEAR AND POOR LOW LEVEL POLEWARDS INFLOW (AS A TROUGH IS SHIFTING IN THE SOUTH). THE SYSTEM SHOULD TRACK WEST-SOUTHWESTWARDS UNDER THE STEERING INFLUENCE OF THE BUILDING SUBTROPICAL HIGH PRESSURES IN THE SOUTHWEST. IT SHOULD THEN SLIGHTLY INTENSIFY (BETTER LOW LEVEL INFLOW, TEMPORARY WEAKENING OF THE VERTICAL WINDSHEAR), WHITOUT REACHING SEVERE TROPICAL STORM STAGE, AS THE SSTS ARE NOT WARM ENOUGH IN THE AREA. WINDS EXTENSION IS MEASURED THANKS TO 0155 UTC QUIKSCAT SWATH.