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 : 6/2/20072008 1.A SEVERE TROPICAL STORM 2 (ARIEL EX-LEE) 2.A POSITION 2007/11/16 AT 1800 UTC : WITHIN 30 NM RADIUS OF POINT 11.8S / 87.3E (ELEVEN DECIMAL EIGHT DEGREES SOUTH AND EIGHTY SEVEN DECIMAL THREE DEGREES EAST) 3.A DVORAK ANALYSIS : 3.0/3.5 /W 0.5/24 H 4.A CENTRAL PRESSURE : 986 HPA 5.A MAX AVERAGE WIND SPEED (10 MN) : 50 KT 6.A EXTENSION OF WINDS BY QUADRANTS (KM): 30 KT NE: 160 SE: 270 SO: 240 NO: 090 50 KT NE: 025 SE: 025 SO: 025 NO: 025 7.A FIRST CLOSED ISOBARE (PRESSURE / AVERAGE DIAM): 1008 HPA / 500 KM 8.A VERTICAL EXTENSION OF CYCLONE CIRCULATION: MEDIUM 1.B FORECASTS: 12H: 2007/11/17 06 UTC: 12.0S/86.4E, MAX WIND=040KT, MODERATE TROP. STORM. 24H: 2007/11/17 18 UTC: 12.3S/85.6E, MAX WIND=035KT, MODERATE TROP. STORM. 36H: 2007/11/18 06 UTC: 12.7S/84.8E, MAX WIND=040KT, MODERATE TROP. STORM. 48H: 2007/11/18 18 UTC: 13.3S/83.9E, MAX WIND=050KT, SEVERE TROP. STORM. 60H: 2007/11/19 06 UTC: 13.3S/82.7E, MAX WIND=060KT, SEVERE TROP. STORM. 72H: 2007/11/19 18 UTC: 13.1S/81.0E, MAX WIND=060KT, SEVERE TROP. STORM. 2.B OTHER INFORMATIONS: T=3.0- AND CI=3.5 SYSTEM KEEPS ON WEAKENING GRADUALLY UNDERGOING A RATHER STRONG NOTHWESTERLY VERTICAL WINDSHEAR (CF 1411Z SSMI/S F16 MICROWAVE IMAGERY) THE SYSTEM WILL REMAIN CLOSE TO HIGH LEVEL STRONG WINDS SOUTH OF 15S BUT MOST GLOBAL MODEL LESSEN THE SHEAR ALONG THE FORECAST TRACK BEYOND 24 HOURS, SYSTEM SHOULD ALSO BEGIN A NEW PHASIS OF INTENSIFICATION. THERE IS SOME SPREAD IN THE MODEL GUIDANCE AT THIS RANGE AS SOME MODELS DEVELOP A LOW NEAR THE CHAGOS AND INTERACT IT WITH ARIEL. AT THIS TIME THIS SCENARIO SEEMS UNREALISTIC. THE FORECAST TRACK IS BASED ON CONSENSUS. WINDS EXTENSION IS CALIBRATED THANKS TO 1210 QUIKSCAT SWATH.