WTIO30 FMEE 130738



RSMC / TROPICAL CYCLONE CENTER / LA REUNION

TROPICAL CYCLONE FORECAST WARNING (SOUTH-WEST INDIAN OCEAN)



0.A WARNING NUMBER: 15/5/20142015

1.A VERY INTENSE TROPICAL CYCLONE  5  (BANSI)



2.A POSITION 2015/01/13 AT 0600 UTC:

WITHIN 10 NM RADIUS OF POINT 17.3 S / 57.6 E

(SEVENTEEN    DECIMAL THREE   DEGREES SOUTH AND FIFTY SEVEN

DECIMAL SIX   DEGREES EAST)

MOVEMENT : EAST 4 KT



3.A DVORAK ANALYSIS: 6.5/7.0/D 1.0/24 H



4.A CENTRAL PRESSURE: 924 HPA

5.A MAX AVERAGE WIND SPEED (10 MN): 120 KT

RADIUS OF MAXIMUM WINDS (RMW) :11 KM



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

28 KT NE: 350 SE: 310 SW: 240 NW: 240

34 KT NE: 220 SE: 190 SW: 190 NW: 170

48 KT NE: 90 SE: 90 SW: 90 NW: 90

64 KT NE: 60 SE: 60 SW: 60 NW: 60



7.A FIRST CLOSED ISOBAR (PRESSURE / AVERAGE DIAM): 1010 HPA / 1300 KM

8.A VERTICAL EXTENSION OF CYCLONE CIRCULATION : DEEP



1.B FORECASTS:

12H: 2015/01/13 18 UTC: 17.3 S / 58.0 E, MAX WIND=115 KT, INTENSE

TROPICAL CYCLONE

24H: 2015/01/14 06 UTC: 17.6 S / 58.6 E, MAX WIND=115 KT, INTENSE

TROPICAL CYCLONE

36H: 2015/01/14 18 UTC: 18.2 S / 59.4 E, MAX WIND=110 KT, INTENSE

TROPICAL CYCLONE

48H: 2015/01/15 06 UTC: 19.0 S / 60.4 E, MAX WIND=110 KT, INTENSE

TROPICAL CYCLONE

60H: 2015/01/15 18 UTC: 20.1 S / 61.8 E, MAX WIND=100 KT, INTENSE

TROPICAL CYCLONE

72H: 2015/01/16 06 UTC: 21.8 S / 63.2 E, MAX WIND=090 KT, INTENSE

TROPICAL CYCLONE



2.B LONGER-RANGE OUTLOOK :

96H: 2015/01/17 06 UTC: 25.7 S / 66.9 E, MAX WIND=075 KT, TROPICAL

CYCLONE

120H: 2015/01/18 06 UTC: 28.5 S / 72.8 E, MAX WIND=065 KT,

POST-TROPICAL DEPRESSION



2.C ADDITIONAL INFORMATIONS:

T=6.5 CI=7.0-.



DURING THE PAST 6 HOURS, EYEWALL HAS SHRUNK AND HAS SLIGHTLY COOLED.

THE INTENSIFICATION TREND HAS STOPPED.



BANSI TRACKS SLOWLY EASTWARD UNDER THE STEERING INFLUENCE OF

MID-LEVEL RIDGE WHICH IS BUILDING NORTH OF THE SYSTEM.

BANSI SHOULD KEEP THIS TRACK DURING THE NEXT 36H AT A QUITE SLOW

SPEED  WITHIN A WEAK STEERING ENVIRONMENT.



ON WEDNESDAY, THE MID-LEVEL RIDGE SHIFTS BACK IN THE EAST OF THE

SYSTEM AND A COL BUILDS IN ITS SOUTH, A SOUTH-EASTWARDS MOTION IS

THEN EXPECTED. BANSI IS THEN EXPECTED TO KEEP ON TRACKING AND

ACCELERATING SOUTH-EASTWARDS UNTIL SATURDAY.



ON THIS FORECAST TRACK, ENVIRONMENTAL CONDITIONS ARE VERY FAVOURABLE

ON TODAY AND WEDNESDAY UNDER THE UPPER LEVEL RIDGE AXIS AS AT LEAST 2

UPPER LEVEL CHANNELS EQUATOR-WARD AND POLEWARD TAKE PLACE WITHIN THE

PERIOD.

FROM THURSDAY, BANSI IS LIKELY TO SHIFT SOUTH OF THE UPPER LEVEL

RIDGE AXIS AND KEEPS ONLY ITS POLEWARD OUTFLOW CHANNEL.



ON FRIDAY,  WESTERLY VERTICAL WINDSHEAR SHOULD STRENGTHEN AND HEAT

OCEANIC CONTENTS WILL WEAKEN. THEREFORE, BANSI SOULD BEGIN TO WEAKEN

SIGNIFICANTLY.



THE INHABITANTS OF MAURITIUS AND RODRIQUES ISLANDS SHOULD THEREFORE

CLOSELY MONITOR THE PROGRESS OF THIS DANGEROUS SYSTEM WITHIN THE NEXT

DAYS.=