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 : 12/11/20052006 1.A MODERATE TROPICAL STORM 11 (DIWA) 2.A POSITION 2006/03/05 AT 0600 UTC : WITHIN 30 NM RADIUS OF POINT 19.5S / 53.7E (NINETEEN DECIMAL FIVE DEGREES SOUTH AND FIFTY THREE DECIMAL SEVEN DEGREES EAST) 3.A DVORAK ANALYSIS : 3.0/3.0 /S 0.0/12 H 4.A CENTRAL PRESSURE : 993 HPA 5.A MAX AVERAGE WIND SPEED (10 MN) : 40 KT 6.A EXTENSION OF WINDS BY QUADRANTS (KM): 30 KT NE: 350 SE: 550 SO: 220 NO: 110 7.A FIRST CLOSED ISOBARE (PRESSURE / AVERAGE DIAM): 1006 HPA / 700 KM 8.A VERTICAL EXTENSION OF CYCLONE CIRCULATION: DEEP 1.B FORECASTS: 12H: 2006/03/05 18 UTC: 20.2S/53.2E, MAX WIND=045KT, MODERATE TROP. STORM. 24H: 2006/03/06 06 UTC: 21.4S/52.4E, MAX WIND=050KT, SEVERE TROP. STORM. 36H: 2006/03/06 18 UTC: 22.9S/52.0E, MAX WIND=060KT, SEVERE TROP. STORM. 48H: 2006/03/07 06 UTC: 23.7S/51.9E, MAX WIND=065KT, TROPICAL CYCLONE. 60H: 2006/03/07 18 UTC: 24.8S/52.4E, MAX WIND=070KT, TROPICAL CYCLONE. 72H: 2006/03/08 06 UTC: 25.9S/53.5E, MAX WIND=070KT, TROPICAL CYCLONE. 2.B OTHER INFORMATIONS: SEA LEVEL PRESSURE HAS DROPPED SIGNIFICANTLY AT REUNION'S ISLAND DURING THE PAST 12 HOURS. THIS FACT CANNOT BE TOTALLY EXPLAINED BY THE EVOLUTION OF THE LOW (ONLY SLIGHTLY CLOSER WITH NO DEEPENING). THEREFORE THERE IS POSSIBILITY THAT A SECONDARY LOW LEVEL CENTER MAY HAVE DEVELOPED SOUTH OF THE MAIN LLCC UNDER THE DEEP CONVECTION (WITH CENTRE NEAR 20.4S/54.3E). THE QUESTION IS NOW TO ASSESS WHETHER THIS SECONDARY LLCC MAY DEEPEN FURTHER AND BECOME THE DOMINANT FEATURE AND MAIN LOW LEVEL CIRCULATION CENTER. IN THIS CASE, THE FORECASTED TRACK SHOULD BE TRANSLATED IN ACCORDANCE WITH THIS POTENTIAL SHIFT. THE RECENT ANIMATED IR-M5 IMAGERY REVEALS THAT THE NORTHWESTERLY CONSTRAINT IS NOW WEAKER AND THE SYSTEM IS EXPECTED TO GAIN FAVOURABLE CONDITIONS FOR A NEW INTENSIFICATION WITHIN 12 TO 24 HOURS.