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 : 9/11/20072008 1.A SEVERE TROPICAL STORM 11 (IVAN) 2.A POSITION 2008/02/09 AT 0600 UTC : 15.8S / 63.0E (FIFTEEN DECIMAL EIGHT DEGREES SOUTH AND SIXTY THREE DECIMAL ZERO DEGREES EAST) 3.A DVORAK ANALYSIS : 4.0/4.0 /D 0.5/24 H 4.A CENTRAL PRESSURE : 975 HPA 5.A MAX AVERAGE WIND SPEED (10 MN) : 60 KT 6.A EXTENSION OF WINDS BY QUADRANTS (KM): 30 KT NE: 150 SE: 180 SO: 180 NO: 180 50 KT NE: 040 SE: 040 SO: 040 NO: 040 7.A FIRST CLOSED ISOBARE (PRESSURE / AVERAGE DIAM): 1006 HPA / 1000 KM 8.A VERTICAL EXTENSION OF CYCLONE CIRCULATION: DEEP 1.B FORECASTS: 12H: 2008/02/09 18 UTC: 15.5S/63.1E, MAX WIND=060KT, SEVERE TROP. STORM. 24H: 2008/02/10 06 UTC: 15.3S/63.2E, MAX WIND=070KT, TROPICAL CYCLONE. 36H: 2008/02/10 18 UTC: 15.1S/63.4E, MAX WIND=070KT, TROPICAL CYCLONE. 48H: 2008/02/11 06 UTC: 15.0S/63.6E, MAX WIND=060KT, SEVERE TROP. STORM. 60H: 2008/02/11 18 UTC: 14.9S/63.8E, MAX WIND=055KT, SEVERE TROP. STORM. 72H: 2008/02/12 06 UTC: 14.7S/63.3E, MAX WIND=050KT, SEVERE TROP. STORM. 2.B OTHER INFORMATIONS: T=4.0 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, TRACK SHOULD TURN NORTHWESTWARDS AS THE SUBTROPICAL RIDGE BUILDS IN THE SOUTHWEST. IF ENVIRONMENTAL CONDITIONS REMAIN RATHER FAVORABLE FOR FURTHER DEVELOPMENT, INTENSITY FLUCTUATIONS ARE STILL POSSIBLE 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.