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
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RSMC / TROPICAL CYCLONE CENTRE / LA REUNION TROPICAL CYCLONE FORECAST WARNING (SOUTH-WEST INDIAN OCEAN) 0.A WARNING NUMBER : 20/4/20072008 1.A MODERATE TROPICAL STORM 4 (CELINA) 2.A POSITION 2007/12/17 AT 0600 UTC : WITHIN 20 NM RADIUS OF POINT 19.5S / 62.0E (NINETEEN DECIMAL FIVE DEGREES SOUTH AND SIXTY TWO DECIMAL ZERO DEGREES EAST) 3.A DVORAK ANALYSIS : 3.0/3.0 /D 0.5/24 H 4.A CENTRAL PRESSURE : 992 HPA 5.A MAX AVERAGE WIND SPEED (10 MN) : 40 KT 6.A EXTENSION OF WINDS BY QUADRANTS (KM): 30 KT NE: 050 SE: 200 SO: 300 NO: 050 7.A FIRST CLOSED ISOBARE (PRESSURE / AVERAGE DIAM): 1006 HPA / 800 KM 8.A VERTICAL EXTENSION OF CYCLONE CIRCULATION: DEEP 1.B FORECASTS: 12H: 2007/12/17 18 UTC: 20.4S/60.3E, MAX WIND=040KT, MODERATE TROP. STORM. 24H: 2007/12/18 06 UTC: 21.3S/58.8E, MAX WIND=035KT, MODERATE TROP. STORM. 36H: 2007/12/18 18 UTC: 22.2S/57.4E, MAX WIND=030KT, TROP. DEPRESSION. 48H: 2007/12/19 06 UTC: 22.9S/56.3E, MAX WIND=030KT, TROP. DEPRESSION. 60H: 2007/12/19 18 UTC: 23.6S/55.2E, MAX WIND=025KT, TROP. DISTURBANCE. 72H: 2007/12/20 06 UTC: 24.0S/54.0E, MAX WIND=025KT, TROP. DISTURBANCE. 2.B OTHER INFORMATIONS: T=3.0- AND CI=3.0 THE SYSTEM HAS ACCELERATED OVER THE LAST 12 HOURS, AS IT TRACKS ALONG THE NORTHWESTERN EDGE OF THE SUBTROPICAL RIDGE CENTRED IN THE SOUTHEAST TOWARDS A TROUGH SHIFTING IN THE SOUTHEAST OF MADAGASCAR. SYSTEM HAS INTENSIFIED DURING LAST NIGHT UNDERGOING A WEAKER VERTICAL WINDSHEAR LINKED TO ITS OWN SPEED WHICH SUBSTRACTS TO THE GENERAL NORTHEASTERLY SHEAR. IT HAS REACHED MODERATE TROPICAL STORM AND HAS BEEN IN CONSEQUENCE NAMED 'CELINA' BY THE MAURTIUS METEOROLOGICAL SERVICES TODAY AT 0430UTC. LAST METEOSAT7 SATELLITE IMAGERY SHOW HOWEVER DIZORGANISATION OF THE DEEP CONVECTIVE ACTIVITY UNDERGOING A DRY ENVIRONMENT, ESPECIALLY AT THE LOWER LEVEL, AS DEPICTED BY MICROWAVE IMAGERY AND COOLER SST. 'CELINA' IS EXPECTED TO KEEPS ON TRACKING RAPIDLY SOUTHWESTWARDS WITHIN THE NEXT 48 HOURS AND THEN RECURVING LINKED TO THE REBUILDING SUBTROPICAL HIGH PRESSURES. SYSTEM HAS PROBABLY REACHED ITS MAXIMUM INTENSITY THEN A WEAKENING IS EXPECTED WITH COOLER SST, A STILL DRY ENVIRONMENT AND WEAKER LOWER LEVEL CONVERGENCE (AS THE MID-LATITUDE TROUGH PASSES SOUTHWARD). WINDS EXTENSION IS ESTIMATED ACCORDING TO 1704 UTC ASCAT SWATH.