WTIO30 FMEE 210636



RSMC / TROPICAL CYCLONE CENTER / LA REUNION

TROPICAL CYCLONE FORECAST WARNING (SOUTH-WEST INDIAN OCEAN)



0.A WARNING NUMBER: 7/1/20152016

1.A MODERATE TROPICAL STORM  1  (ANNABELLE)



2.A POSITION 2015/11/21 AT 0600 UTC:

WITHIN 20 NM RADIUS OF POINT 10.3 S / 71.2 E

(TEN    DECIMAL THREE   DEGREES SOUTH AND SEVENTY ONE    DECIMAL TWO

DEGREES EAST)

MOVEMENT : SOUTH-WEST 3 KT



3.A DVORAK ANALYSIS: 3.0/3.0/D 0.5/12 H



4.A CENTRAL PRESSURE: 993 HPA

5.A MAX AVERAGE WIND SPEED (10 MN): 40 KT

RADIUS OF MAXIMUM WINDS (RMW) :46 KM



6.A EXTENSION OF WIND BY QUADRANTS (KM):

28 KT NE: 190 SE: 190 SW: 190 NW: 150

34 KT NE: 90 SE: 90 SW: 90 NW: 90







7.A FIRST CLOSED ISOBAR (PRESSURE / AVERAGE DIAM): 1007 HPA / 600 KM

8.A VERTICAL EXTENSION OF CYCLONE CIRCULATION : DEEP



1.B FORECASTS:

12H: 2015/11/21 18 UTC: 11.1 S / 71.0 E, MAX WIND=050 KT, SEVERE

TROPICAL STORM

24H: 2015/11/22 06 UTC: 12.4 S / 71.3 E, MAX WIND=050 KT, SEVERE

TROPICAL STORM

36H: 2015/11/22 18 UTC: 13.6 S / 72.1 E, MAX WIND=040 KT, MODERATE

TROPICAL STORM

48H: 2015/11/23 06 UTC: 15.0 S / 73.6 E, MAX WIND=030 KT, TROPICAL

DEPRESSION

60H: 2015/11/23 18 UTC: 16.4 S / 74.7 E, MAX WIND=030 KT, TROPICAL

DEPRESSION

72H: 2015/11/24 06 UTC: 17.7 S / 75.8 E, MAX WIND=025 KT, LOW



2.B LONGER-RANGE OUTLOOK :

96H: 2015/11/25 06 UTC: 19.0 S / 73.2 E, MAX WIND=020 KT, DISSIPATING

120H: 2015/11/26 06 UTC: 19.2 S / 70.2 E, MAX WIND=020 KT,

DISSIPATING



2.C ADDITIONAL INFORMATION:

FT=CI=3.0+



DURING THE LAST 6 HOURS, DEEP CONVECTION HAS DEVELOPED OVER THE

CENTER INTO A CURVED BAND.



THE CURRENT SOUTHWESTWARDS TRACK IS SLOW DURING THE NEXT HOURS, ALL

AVAILABLE NWP FORECAST TRACK TO BEND TOWARDS A WEAKNESS IN THE

PRESSURE FIELD TO THE SOUTH OF THE SYSTEM.

AN EQUATORIAL MID LEVEL RIDGE IS EXPECTED TO BUILD IN THE

EAST-NORTH-EAST OF THE SYSTEM AND SHOULD GRADUALLY STEERED THE SYSTEM

SOUTHEASTWARDS FROM THIS NIGHT AND BEYOND WITH A GRADUAL INCREASE IN

FORWARD MOTION.



ALONG THIS TRACK, ENVIRONMENTAL CONDITIONS REMAIN FAVOURABLE WITH A

GOOD UPPER LEVEL DIVERGENCE, WEAK VERTICAL WINDSHEAR AND ONE POLAR

OUTFLOW CHANNEL. THIS WINDOW FOR INTENSIFICATION SHOULD ALLOW THE

SYSTEM TO GRADUALLY STRENGTHEN UP TO THE GREATER STAGE OF TROPICAL

STORM.

BUT ON SUNDAY, NORTHERLY VERTICAL WINDSHEAR SHOULD INCREASE AHEAD A

UPPER LEVEL TROUGH AND THE SYSTEM SHOULD QUICKLY WEAKEN. MOREOVER,

THE HEAT CONTENT WIIL BECOME MARGINAL SOUTH OF 13S. ON TUESDAY, THE

RESIDUAL LOW SHOULD TRACK EASTWARDS IN THE TRADES FLOW FILLING UP

PROGRESSIVELY.=