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 : 10/11/20072008 1.A SEVERE TROPICAL STORM 11 (IVAN) 2.A POSITION 2008/02/09 AT 1200 UTC : 15.7S / 63.1E (FIFTEEN DECIMAL SEVEN DEGREES SOUTH AND SIXTY THREE DECIMAL ONE DEGREES EAST) 3.A DVORAK ANALYSIS : 4.0/4.0 /S 4.A CENTRAL PRESSURE : 980 HPA 5.A MAX AVERAGE WIND SPEED (10 MN) : 55 KT 6.A EXTENSION OF WINDS BY QUADRANTS (KM): 30 KT NE: 150 SE: 150 SO: 150 NO: 150 50 KT NE: 030 SE: 030 SO: 030 NO: 030 7.A FIRST CLOSED ISOBARE (PRESSURE / AVERAGE DIAM): 1006 HPA / 1000 KM 8.A VERTICAL EXTENSION OF CYCLONE CIRCULATION: DEEP 1.B FORECASTS: 12H: 2008/02/10 00 UTC: 15.5S/63.2E, MAX WIND=060KT, SEVERE TROP. STORM. 24H: 2008/02/10 12 UTC: 15.3S/63.4E, MAX WIND=060KT, SEVERE TROP. STORM. 36H: 2008/02/11 00 UTC: 15.2S/63.7E, MAX WIND=070KT, TROPICAL CYCLONE. 48H: 2008/02/11 12 UTC: 15.1S/63.9E, MAX WIND=060KT, SEVERE TROP. STORM. 60H: 2008/02/12 00 UTC: 15.0S/63.7E, MAX WIND=055KT, SEVERE TROP. STORM. 72H: 2008/02/12 12 UTC: 14.8S/63.2E, MAX WIND=050KT, SEVERE TROP. STORM. 2.B OTHER INFORMATIONS: T=CI=4.0- AVAILABLE NWP MODELS ARE STILL NOT IN GOOD AGREEMENT WITH IVAN'S EVOLUTION AND SHOW A LARGE SPREAD. IVAN IS IN A VERY WEAK STEERING ENVIRONEMENT AND SHOULD KEEP ON TRACKING VERY SLOWLY NORTHWARD TO NORTHEASTERNWARDS. ON MONDAY 11, TRACK SHOULD TURN NORTHWESTWARDS AS THE SUBTROPICAL RIDGE BUILDS IN THE SOUTHWEST. IF ENVIRONMENTAL CONDITIONS REMAIN RATHER FAVORABLE FOR FURTHER DEVELOPMENT, INTESIFICATION IS EMPEDED IF THE SYSTEM REMAINS QUASI-STATIONARY QUITE A LONG TIME. GIVEN THE WIDE SPREAD IN NWM SOLUTIONS, IT IS A LOWER THAN AVERAGE DEGREE OF CONFIDENCE IN THIS FORECAST.