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 : 27/11/20072008 1.A MODERATE TROPICAL STORM 11 (IVAN) 2.A POSITION 2008/02/13 AT 1800 UTC : WITHIN 20 NM RADIUS OF POINT 13.4S / 61.0E (THIRTEEN DECIMAL FOUR DEGREES SOUTH AND SIXTY ONE DECIMAL ZERO DEGREES EAST) 3.A DVORAK ANALYSIS : 3.5/3.5 /D 1.0/24 H 4.A CENTRAL PRESSURE : 985 HPA 5.A MAX AVERAGE WIND SPEED (10 MN) : 45 KT 6.A EXTENSION OF WINDS BY QUADRANTS (KM): 30 KT NE: 200 SE: 180 SO: 150 NO: 250 7.A FIRST CLOSED ISOBARE (PRESSURE / AVERAGE DIAM): 1007 HPA / 1000 KM 8.A VERTICAL EXTENSION OF CYCLONE CIRCULATION: DEEP 1.B FORECASTS: 12H: 2008/02/14 06 UTC: 13.7S/59.3E, MAX WIND=055KT, SEVERE TROP. STORM. 24H: 2008/02/14 18 UTC: 14.1S/57.6E, MAX WIND=065KT, TROPICAL CYCLONE. 36H: 2008/02/15 06 UTC: 14.6S/55.9E, MAX WIND=075KT, TROPICAL CYCLONE. 48H: 2008/02/15 18 UTC: 15.0S/55.0E, MAX WIND=085KT, TROPICAL CYCLONE. 60H: 2008/02/16 06 UTC: 15.4S/54.5E, MAX WIND=090KT, INTENSE TROP. CYCL.. 72H: 2008/02/16 18 UTC: 16.0S/54.0E, MAX WIND=090KT, INTENSE TROP. CYCL.. 2.B OTHER INFORMATIONS: T=CI=3.5- IVAN HAS TRACKED WEST-NORTHWESTWARDS 6 KNOTS OVER THE LAST 12 HOURS. LATEST AVAILABLE MICROWAVE IMAGERY, F15 13/1512Z SHOWS A BUILDING DEEP CONVECTION -EVEN STILL RATHER ERODED IN THE SOUTHEASTERN SEMI-CIRCLE, AND DISPLAYS A WELL DEFINED UPPER LEVEL CENTRE, NORTHWESTWARDS AWAY FROM LLCC. THE SYSTEM SHOULD GENERALLY TRACK WESTWARDS ALONG THE NORTHERN EDGE OF THE SUBTROPICAL RIDGE BECOMING THE PRIMARY STEERING FLOW. IT SHOULD THEN KEEP ON REGULARLY INTENSIFYING WITHIN A MORE FAVORABLE ENVIRONMENT, UNDER THE UPPER LEVEL RIDGE (WEAKER EASTERLY SHEAR) AND WESR OF 60E, FAR FROM THE AREA OF LOWER OCEAN HEAT CONTENT. ON FRIDAY 15, IVAN IS FORECASTED TO GRADUALLY CURVE ON A MORE POLEWARDS TRACK AS THE SUBTROPICAL RIDGE WEAKENS AND A MID-TROPOSPHERIC RIDGE IS BUILDING NORT-EAST OF THE SYSTEM. SPEED MOVEMENT SHOULD THEN SLIGHTY DECREASE. AVAILABLE DYNAMIC AIDS ARE IN BETTER AGREEMENT AND THIS FORECAST IS CLOSE TO THE ECMWF AND A CONSENSUS OF AMERICAN MODELS.