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 : 24/12/20082009 1.A TROPICAL DEPRESSION 12 (EX-JADE) 2.A POSITION 2009/04/10 AT 0000 UTC : WITHIN 30 NM RADIUS OF POINT 23.1S / 50.9E (TWENTY THREE DECIMAL ONE DEGREES SOUTH AND FIFTY DECIMAL NINE DEGREES EAST) MOVEMENT : SOUTH-EAST 5 KT 3.A DVORAK ANALYSIS : 2.0/2.5 /S 0.0/6 H 4.A CENTRAL PRESSURE : 997 HPA 5.A MAX AVERAGE WIND SPEED (10 MN) : 30 KT RADIUS OF MAXIMUM WINDS (RMW) : NIL 6.A EXTENSION OF WINDS BY QUADRANTS (KM): 30 KT NE: 250 SE: 360 SO: 250 NO: 200 7.A FIRST CLOSED ISOBARE (PRESSURE / AVERAGE DIAM): 1006 HPA / 700 KM 8.A VERTICAL EXTENSION OF CYCLONE CIRCULATION: SHALLOW 1.B FORECASTS: 12H: 2009/04/10 12 UTC: 24.1S/52.0E, MAX WIND=030KT, TROP. DEPRESSION. 24H: 2009/04/11 00 UTC: 26.0S/54.0E, MAX WIND=030KT, BECOMING EXTRATROPICAL. 36H: 2009/04/11 12 UTC: 30.5S/56.6E, MAX WIND=040KT, EXTRATROPICAL. 48H: 2009/04/12 00 UTC: 35.3S/57.6E, MAX WIND=045KT, EXTRATROPICAL. 60H: 2009/04/12 12 UTC: 39.2S/60.6E, MAX WIND=050KT, EXTRATROPICAL. 72H: 2009/04/13 00 UTC: 43.4S/66.8E, MAX WIND=045KT, EXTRATROPICAL. 2.B OTHER INFORMATIONS: T=2.0, CI=2.5 CONVECTIVE ACTIVITY PERSISTS SOUTHEAST OF THE SYSTEM DUE TO A LOWER LEVELS CONVERGENCE AXIS AND FAVOURED BY UPPER LEVELS DIFFLUENCE DUE TO THE POLAR JETSTREAM APPORCHING. IT IS EXPECTED TO WEAKEN PROGRESSIVELY ON FRIDAY, AS THE SYSTEM IS TRACKING AVER COOLER SST AND THE UPPER LEVELS WIND SHEAR IS INCREASING. STRONGER WINDS ARE NOW LOCATED AT MORE THAN 30MN FROM THE LLCC (CF. QUIKSCAT DATA AT 14.53Z). THEY LOCALLY REACH THE GALE FORCE WIND IN THE WESTERN SEMI-CIRCLE AND PROBABLY IN THE EASTERN SEMI-CIRCLE DUE TO THE OWN SYSTEM MOTION AND THE GRADIENT EFFECT WITH THE SUBTROPICAL HIGHS. THIS WINDS PATTREN SHOULD REMAIN DURING THE NEXT 24 HOURS AND WINDS ARE EXPECTED TO INCREASE WHEN THE SYSTEM WILL MERGE WITH A MID LATITUDES TROUGH. THE SYSTEM IS EXPECTED TO KEEPS ON TRACKING GLOBALLY SOUTHEASTWARDS SPEEDING UP ATFER FRIDAY AFTERNOON DUE TO THE HIGH PRESSURE MOVING EATSWARD AND THE TROUGH ARRIVING IN THE SOUTH. IT IS EXPECTED TO BEGIN ITS EXTRATROPICAL TRANSITION DURING THE NEXT 24 HOURS AND CONTINUE TO ACCELERATE SOUTHEASTWARD BEYOND.