WTIO30 FMEE 151912



RSMC / TROPICAL CYCLONE CENTER / LA REUNION

TROPICAL CYCLONE FORECAST WARNING (SOUTH-WEST INDIAN OCEAN)



0.A WARNING NUMBER: 25/5/20142015

1.A INTENSE TROPICAL CYCLONE  5  (BANSI)



2.A POSITION 2015/01/15 AT 1800 UTC:

WITHIN 20 NM RADIUS OF POINT 18.2 S / 63.0 E

(EIGHTEEN    DECIMAL TWO   DEGREES SOUTH AND SIXTY THREE    DECIMAL

ZERO   DEGREES EAST)

MOVEMENT : EAST-SOUTH-EAST 11 KT



3.A DVORAK ANALYSIS: 6.0/6.0/D 1.0/6 H



4.A CENTRAL PRESSURE: 940 HPA

5.A MAX AVERAGE WIND SPEED (10 MN): 100 KT

RADIUS OF MAXIMUM WINDS (RMW) :39 KM



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

28 KT NE: 350 SE: 220 SW: 220 NW: 460

34 KT NE: 300 SE: 190 SW: 190 NW: 260

48 KT NE: 200 SE: 150 SW: 130 NW: 190

64 KT NE: 120 SE: 100 SW: 70 NW: 120



7.A FIRST CLOSED ISOBAR (PRESSURE / AVERAGE DIAM): 1004 HPA / 1100 KM

8.A VERTICAL EXTENSION OF CYCLONE CIRCULATION : DEEP



1.B FORECASTS:

12H: 2015/01/16 06 UTC: 19.6 S / 65.3 E, MAX WIND=095 KT, INTENSE

TROPICAL CYCLONE

24H: 2015/01/16 18 UTC: 21.7 S / 67.0 E, MAX WIND=095 KT, INTENSE

TROPICAL CYCLONE

36H: 2015/01/17 06 UTC: 23.0 S / 68.2 E, MAX WIND=090 KT, INTENSE

TROPICAL CYCLONE

48H: 2015/01/17 18 UTC: 24.0 S / 70.0 E, MAX WIND=085 KT, TROPICAL

CYCLONE

60H: 2015/01/18 06 UTC: 24.6 S / 72.7 E, MAX WIND=080 KT,

POST-TROPICAL DEPRESSION

72H: 2015/01/18 18 UTC: 24.9 S / 76.4 E, MAX WIND=080 KT,

POST-TROPICAL DEPRESSION



2.B LONGER-RANGE OUTLOOK :

96H: 2015/01/19 18 UTC: 28.2 S / 81.9 E, MAX WIND=060 KT,

POST-TROPICAL DEPRESSION

120H: 2015/01/20 18 UTC: 30.1 S / 81.8 E, MAX WIND=050 KT,

POST-TROPICAL DEPRESSION



2.C ADDITIONAL INFORMATIONS:

T=6.0 AND CI=6.0



AS EXPECTED, BANSI IS EXPERIENCING A NEW INTENSIFICATION PHASIS.

IT HAS GLOBALLY TRACKED EASTWARDS UNTIL 14Z THEN RECURVED

EAST-SOUTH-EASTWARDS AFTERTHAT.

THIS LATE TRACK'S INFLEXION IS A RELATIVELY GOOD NEWS FOR RODRIGUES

ISLAND WITH A CLOSEST POINT APPROACH AT ABOUT 100 KM OR MORE FROM THE

SHORELINE AT THE END OF THIS NIGHT.



BANSI IS FORECAST TO ACCELERATE PROGRESSIVELY ON THIS

EAST-SOUTH-EASTWARDS THEN SOUTH-EASTWARDS TRACK, UNDER THE STEERING

INFLUENCE OF A NEAR EQUATORIAL RIDGE AND OF A RIDGE BUILDING

EASTWARD, IN THE MID TO HIGH LEVELS.

THE AVAILABLE NWP MODELS ARE IN GOOD AGREEMENT FOR THIS TRACK.



ON THIS TRACK, THE SYSTEM SHOULD KEEP ON WITH FAVORABLE UPPER LEVEL

ENVIRONMENT FOR THIS NIGHT, WITH LOW VERTICAL WINDSHEAR, AND GOOD

POLEWARD OUTFLOW.

ON FRIDAY, BANSI SHOULD PROGRESS SOUTH OF THE UPPER LEVEL RIDGE AXIS,

AND AN UPPER LEVEL TROUGH SHOULD COME CLOSER THE SYSTEM FROM THE

SOUTH-WEST. THE UPPER LEVEL WESTERLY WINDSHEAR SHOULD INCREASE. OWING

TO THE LOWERING OF THE OCEANIC HEAT POTENTIAL ON THE SYSTEM TRACK

ROUND 25S, BANSI IS LIKELY TO BECOME A POST-TROPICAL HYBRID SYSTEM

FROM SUNDAY. HOWEVER, THE MAXIMUM WIND SPEED IS LIKELY TO REMAIN

STRONG WITHIN THE LOW LEVEL CIRCULATION.



THEREFORE, THE INHABITANTS OF RODRIGUES ISLAND (INCREASING THREAT

WITH SEVERE WEATHER CONDITIONS FOR THE NEXT NIGHT) SHOULD CLOSELY

MONITOR THE PROGRESS OF THIS DANGEROUS SYSTEM.=