Direction Interrégionale de LA REUNION
B.P.4    97491 Ste Clotilde Cedex
Téléphone                02.62.92.11.00
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RSMC / TROPICAL CYCLONE CENTRE / LA REUNION TROPICAL CYCLONE FORECAST WARNING (SOUTH-WEST INDIAN OCEAN) 0.A WARNING NUMBER : 8/3/20072008 1.A SEVERE TROPICAL STORM 3 (BONGWE) 2.A POSITION 2007/11/20 AT 0600 UTC : WITHIN 30 NM RADIUS OF POINT 11.6S / 75.5E (ELEVEN DECIMAL SIX DEGREES SOUTH AND SEVENTY FIVE DECIMAL FIVE DEGREES EAST) 3.A DVORAK ANALYSIS : 3.5/4.0 /D 0.5/24 H 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: 100 SE: 150 SO: 250 NO: 250 50 KT NE: 030 SE: 030 SO: 030 NO: 030 7.A FIRST CLOSED ISOBARE (PRESSURE / AVERAGE DIAM): 1010 HPA 8.A VERTICAL EXTENSION OF CYCLONE CIRCULATION: DEEP 1.B FORECASTS: 12H: 2007/11/20 18 UTC: 12.3S/74.1E, MAX WIND=060KT, SEVERE TROP. STORM. 24H: 2007/11/21 06 UTC: 12.8S/72.9E, MAX WIND=060KT, SEVERE TROP. STORM. 36H: 2007/11/21 18 UTC: 13.3S/72.0E, MAX WIND=065KT, TROPICAL CYCLONE. 48H: 2007/11/22 06 UTC: 13.5S/71.2E, MAX WIND=065KT, TROPICAL CYCLONE. 60H: 2007/11/22 18 UTC: 13.6S/70.7E, MAX WIND=065KT, TROPICAL CYCLONE. 72H: 2007/11/23 06 UTC: 13.6S/70.1E, MAX WIND=065KT, TROPICAL CYCLONE. 2.B OTHER INFORMATIONS: T=3.5 AND CI=4.0- AFTER A RATHER GOOD PRESENTATION LAST NIGHT ON THE MICROWAVE IMAGERY, WINDSAT PASS AT 0038Z SHOWS AGAIN A SLIGHT TILT IN THE INNER CIRCULATION DUE TO EASTERLY SHEAR. AS THIS SHEAR IS FORCAST TO MAINTAIN FOR THE NEXT 24 HOURS BEFORE LESSEN A LITTE BIT, FORCAST INTENSITY HAS BEEN ADJUSTED AND CALL NOW FOR A SLIGHT STRENGHENING AT TROPICAL CYCLONE STAGE AT H+36 ... NWP ARE ALL AGREE FOR THE CONTINUING SOUTWESTWARDS TRACK UNTIL H+36 .. AFTER THAT SOME RELIABLE MODELS (AS GFDN, GFS) RECURVE THE TRACK SOUTH-EASTWARDS AS "BONGWE" COULD BE AGAIN ON THE INFLUENCE OF THE MID-LEVEL RIDGE THAT IS STILL NORTH-EAST OF THE SYSTEM. THE PRESENT GUIDANCE FOLLOWS THE ECMWF AND EPS TRACKS WITH A WESTWARDS TRACK, BUT SLOW DOWN "BONGWE" AT DAY 3.