WTIO30 FMEE 180642



RSMC / TROPICAL CYCLONE CENTER / LA REUNION

TROPICAL CYCLONE FORECAST WARNING (SOUTH-WEST INDIAN OCEAN)



0.A WARNING NUMBER: 35/5/20142015

1.A SEVERE TROPICAL STORM  5  (BANSI)



2.A POSITION 2015/01/18 AT 0600 UTC:

WITHIN 30 NM RADIUS OF POINT 25.0 S / 75.8 E

(TWENTY FIVE    DECIMAL ZERO   DEGREES SOUTH AND SEVENTY FIVE

DECIMAL EIGHT   DEGREES EAST)

MOVEMENT : EAST 20 KT



3.A DVORAK ANALYSIS: 3.0/4.0/W 0.5/24 H



4.A CENTRAL PRESSURE: 958 HPA

5.A MAX AVERAGE WIND SPEED (10 MN): 60 KT

RADIUS OF MAXIMUM WINDS (RMW) :56 KM



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

28 KT NE: 460 SE: 1,150 SW: 1,390 NW: 410

34 KT NE: 370 SE: 370 SW: 670 NW: 330

48 KT NE: 170 SE: 190 SW: 220 NW: 110





7.A FIRST CLOSED ISOBAR (PRESSURE / AVERAGE DIAM): 996 HPA / 600 KM

8.A VERTICAL EXTENSION OF CYCLONE CIRCULATION : DEEP



1.B FORECASTS:

12H: 2015/01/18 18 UTC: 26.8 S / 82.2 E, MAX WIND=000 , SEVERE

TROPICAL STORM

24H: 2015/01/19 06 UTC: 30.0 S / 87.5 E, MAX WIND=000 , POST-TROPICAL

DEPRESSION

36H: 2015/01/19 18 UTC: 33.7 S / 92.6 E, MAX WIND=000 , EXTRATROPICAL

SYSTEM

48H: 2015/01/20 06 UTC: 35.5 S / 98.6 E, MAX WIND=000 , EXTRATROPICAL

SYSTEM







2.B LONGER-RANGE OUTLOOK :







2.C ADDITIONAL INFORMATIONS:

T=3.0+ AND CI=4.0+



LOW LEVEL CIRCULATION IS NOW PARTIALLY EXPOSED ON THE NORTH-WESTERN

EDGE OF THE DEEP CONVECTIVE ACTIVITY.



TODAY, BANSI WILL REMAIN ON A FAST EAST-SOUTH-EAST TRACK UNDER THE

DUAL STEERING INFLUENCE OF THE MID-LEVEL HIGHS LOCATED IN ITS

NORTH-EAST AND NORTH AND A HIGH TO MID-LEVEL MID-LAT TROUGH LOCATED

TO THE SOUTH-OUTH-EAST OF BANSI AND WELL DEPICT ON WV IMAGERY EAST OF

70E.



ON THIS PATH, THE UPPER LEVEL WESTERLY WINDSHEAR, AND THE LOWERING OF

THE OCEANIC HEAT POTENTIAL ABOUT 25S, WILL BECOME MORE AND MORE

UNFAVORABLE TO THE SYSTEM. BANSI SHOULD BEGIN ITS EXTRATROPICAL

TRASITION WITHIN THE NEXT 24 HOURS.

FROM MONDAY, IT SHOULD TRACK SOUTH-EASTWARD UNDER THE STEERING

INFLUENCE OF THE AFOREMENTIONED TROUGH.

ON TUESDAY, THE LOW LEVEL CIRCULATION IS LIKELY TO MERGE WITH THE

MID-LATITUDES TROUGH AND ASSOCIATED COLD FRONT.



WINDS ARE EXPECTED TO REMAIN STRONG WITHIN BANSI UNTIL ITS FINAL

MERGING WITH THE COLD FRONT.=