WTIO30 FMEE 160139



RSMC / TROPICAL CYCLONE CENTER / LA REUNION

TROPICAL CYCLONE FORECAST WARNING (SOUTH-WEST INDIAN OCEAN)



0.A WARNING NUMBER: 26/5/20142015

1.A INTENSE TROPICAL CYCLONE  5  (BANSI)



2.A POSITION 2015/01/16 AT 0000 UTC:

WITHIN 20 NM RADIUS OF POINT 19.1 S / 64.2 E

(NINETEEN    DECIMAL ONE   DEGREES SOUTH AND SIXTY FOUR    DECIMAL

TWO   DEGREES EAST)

MOVEMENT : SOUTH-EAST 14 KT



3.A DVORAK ANALYSIS: 6.5/6.5/D 1.5/12 H



4.A CENTRAL PRESSURE: 923 HPA

5.A MAX AVERAGE WIND SPEED (10 MN): 115 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: 90 NW: 190

64 KT NE: 140 SE: 110 SW: 70 NW: 130



7.A FIRST CLOSED ISOBAR (PRESSURE / AVERAGE DIAM): 1003 HPA / 1100 KM

8.A VERTICAL EXTENSION OF CYCLONE CIRCULATION : DEEP



1.B FORECASTS:

12H: 2015/01/16 12 UTC: 21.4 S / 66.2 E, MAX WIND=110 KT, INTENSE

TROPICAL CYCLONE

24H: 2015/01/17 00 UTC: 22.9 S / 67.7 E, MAX WIND=100 KT, INTENSE

TROPICAL CYCLONE

36H: 2015/01/17 12 UTC: 23.8 S / 69.8 E, MAX WIND=090 KT, INTENSE

TROPICAL CYCLONE

48H: 2015/01/18 00 UTC: 24.3 S / 72.0 E, MAX WIND=080 KT, TROPICAL

CYCLONE

60H: 2015/01/18 12 UTC: 24.3 S / 74.1 E, MAX WIND=080 KT,

POST-TROPICAL DEPRESSION

72H: 2015/01/19 00 UTC: 24.5 S / 76.8 E, MAX WIND=070 KT,

POST-TROPICAL DEPRESSION



2.B LONGER-RANGE OUTLOOK :

96H: 2015/01/20 00 UTC: 27.1 S / 79.7 E, MAX WIND=060 KT,

POST-TROPICAL DEPRESSION

120H: 2015/01/21 00 UTC: 31.3 S / 81.2 E, MAX WIND=050 KT,

POST-TROPICAL DEPRESSION



2.C ADDITIONAL INFORMATIONS:

T=6.5+ AND CI=6.5+



BANSI KEPT ON INTENSIFYING WITHIN THE LAST 6 HOURS AND IS

ACCELERATING SOUTH-EASTWARDS UNDER THE STEERING INFLUENCE OF A NEAR

EQUATORIAL RIDGE AND OF A RIDGE BUILDING EASTWARD,



THANKS TO ITS LATE MOTION'S CHANGE SOUTH-EASTWARDS, BANSI WAS AT ITS

CLOSEST POINT APPROACH FROM THE RODRIGUES ISLAND SHORELINE AT 03Z AND

IS NOW ROLLING AWAY.

AT THIS DISTANCE, IN THE SOUTH-WESTERN SEMI-CIRCLE (THE LESS

DANGEROUS) AND DISPITE THE AFOREMENTIONED INTENSIFICATION AND VERY

DEGRADED WEATHER CONDITIONS, RODRIGUES ISLAND ESCAPED TO THE WORST.

BAD CONDITIONS SHOULD HOWEVER PERSIST WITHIN THE NEXT 12 HOURS AND

BECOME TO SLOWLY IMPROVE NEXT NIGHT.



BANSI IS EXPECTED TO KEEP ON TRACKING SOUTH-EASTWARDS UNTIL SATURDAY

THEN EASTWARDS ON SUNDAY AND TO EVACUATE SOUTH-SOUTH-EASTWARDS ON AND

AFTER MONDDAY.

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



ON THIS FORECAST TRACK, SYSTEM PROGRESS SOUTH OF THE UPPER LEVEL

RIDGE AXIS, AND AN UPPER LEVEL TROUGH SHOULD COME CLOSER TO THE

SYSTEM FROM THE SOUTH-WEST.

WESTERLY VERTICAL WINDSHEAR IS CONSEQUENTLY EXPECTED TO INCREASE AND

IN RELATIONSHIP WITH LOWER OCEANIC HEAT CONTENTS NEAR 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.=