Back to the RSMC advisories list
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 : 11/4/20072008
1.A TROPICAL DEPRESSION 4 (0420072008)

2.A POSITION 2007/12/15 AT 0000 UTC :
WITHIN 30 NM RADIUS OF POINT 15.2S / 69.0E
(FIFTEEN DECIMAL TWO DEGREES SOUTH AND SIXTY NINE DECIMAL ZERO DEGREES EAST)

3.A DVORAK ANALYSIS : 2.5/2.5 /S 0.0/24 H
4.A CENTRAL PRESSURE : 999 HPA
5.A MAX AVERAGE WIND SPEED (10 MN) : 30 KT

6.A EXTENSION OF WINDS BY QUADRANTS (KM):
30 KT NE: 130 SE: 290 SO: 280 NO: 175

7.A FIRST CLOSED ISOBARE (PRESSURE / AVERAGE DIAM): 1002 HPA / 800 KM
8.A VERTICAL EXTENSION OF CYCLONE CIRCULATION: MEDIUM

1.B FORECASTS:
12H: 2007/12/15 12 UTC: 15.9S/68.1E, MAX WIND=030KT, TROP. DEPRESSION.
24H: 2007/12/16 00 UTC: 16.3S/66.7E, MAX WIND=030KT, TROP. DEPRESSION.
36H: 2007/12/16 12 UTC: 16.7S/65.3E, MAX WIND=035KT, MODERATE TROP. STORM.
48H: 2007/12/17 00 UTC: 17.3S/63.8E, MAX WIND=040KT, MODERATE TROP. STORM.
60H: 2007/12/17 12 UTC: 17.8S/62.4E, MAX WIND=040KT, MODERATE TROP. STORM.
72H: 2007/12/18 00 UTC: 18.7S/61.5E, MAX WIND=040KT, MODERATE TROP. STORM.

2.B OTHER INFORMATIONS:
T AND CI=2.5-
THE LOW LEVEL CIRCULATION REMAINS PARTIALLY EXPOSED, BUT LLCC IS NOT MORE REVEALED ON METEOSAT7 INFRARED SATELLITE IMAGERY.
SYSTEM UNDERGOES A NORTHEASTERLY CONSTRAINT WHICH EJECTS ACTIVE DEEP CONVECTION SOUTHWESTSWARDS.
CONDITIONS ARE POORLY FAVOURABLE FOR INTENSIFICATION, DUE TO MODERATE VERTICAL WINDSHEAR, POOR LOW LEVEL TRADEWINDS INFLOW (TROUGH TO THE SOUTH), WEAK UPPER LEVEL DIVERGENCE.
THE SYSTEM SHOULD ACCELERATE SOUTHWESTWARDS UNDER THE STEERING INFLUENCE OF A MIDLEVEL SUBTROPICAL RIDGE TO THE SOUTHEAST.
IT SHOULD THEN INTENSIFY LIGHTLY (BETTER LOW LEVEL INFLOW, TEMPORARY WEAKENING OF THE VERTICAL WINDSHEAR), WHITOUT REACHING SEVERE TROPICAL STORM STAGE.
WINDS EXTENTION IS CALIBRATED THANKS TO 1325UTC QUIKSCAT SWATH.