WTIO30 FMEE 191833



RSMC / TROPICAL CYCLONE CENTER / LA REUNION

TROPICAL CYCLONE FORECAST WARNING (SOUTH-WEST INDIAN OCEAN)



0.A WARNING NUMBER: 35/8/20152016

1.A TROPICAL CYCLONE  8  (FANTALA)



2.A POSITION 2016/04/19 AT 1800 UTC:

WITHIN 20 NM RADIUS OF POINT 9.7 S / 51.1 E

(NINE    DECIMAL SEVEN   DEGREES SOUTH AND FIFTY ONE    DECIMAL ONE

DEGREES EAST)

MOVEMENT : EAST-SOUTH-EAST 6 KT



3.A DVORAK ANALYSIS: 4.0/4.5/S 0.0/6 H



4.A CENTRAL PRESSURE: 976 HPA

5.A MAX AVERAGE WIND SPEED (10 MN): 70 KT

RADIUS OF MAXIMUM WINDS (RMW) :33 KM



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

28 KT NE: 240 SE: 250 SW: 240 NW: 280

34 KT NE: 150 SE: 70 SW: 90 NW: 120

48 KT NE: 100 SE: 60 SW: 70 NW: 90

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



7.A FIRST CLOSED ISOBAR (PRESSURE / AVERAGE DIAM): 0  / 0 KM

8.A VERTICAL EXTENSION OF CYCLONE CIRCULATION : DEEP



1.B FORECASTS:

12H: 2016/04/20 06 UTC: 10.2 S / 52.2 E, MAX WIND=070 KT, TROPICAL

CYCLONE

24H: 2016/04/20 18 UTC: 11.0 S / 53.2 E, MAX WIND=055 KT, SEVERE

TROPICAL STORM

36H: 2016/04/21 06 UTC: 11.8 S / 54.1 E, MAX WIND=045 KT, MODERATE

TROPICAL STORM

48H: 2016/04/21 18 UTC: 12.7 S / 54.7 E, MAX WIND=040 KT, MODERATE

TROPICAL STORM

60H: 2016/04/22 06 UTC: 13.0 S / 55.0 E, MAX WIND=040 KT, MODERATE

TROPICAL STORM

72H: 2016/04/22 18 UTC: 12.9 S / 54.6 E, MAX WIND=040 KT, MODERATE

TROPICAL STORM



2.B LONGER-RANGE OUTLOOK :

96H: 2016/04/23 18 UTC: 11.9 S / 52.3 E, MAX WIND=045 KT, MODERATE

TROPICAL STORM

120H: 2016/04/24 18 UTC: 10.9 S / 50.0 E, MAX WIND=045 KT, MODERATE

TROPICAL STORM



2.C ADDITIONAL INFORMATION:

T=4.0+ CI=4.5



THE VERY LAST IR PICTURES SHOW AN IMPROVEMENT OF THE CLOUD PATTERN,

MORE SYMMETRIC. THE 3H MEAN DT IS 4.0+.

THE MW PICTURES SSMIS AT 1258Z AND GPM AT 1346Z SHOW A DEEP AND

SYMMETRIC CONVECTIVE RING.



UNTIL THURSDAY, FANTALA'S TRACK WILL BE STEERED BY TWO ATMOSPHERIC

PATTERNS : THE NEAR EQUATORIAL RIDGE BUILDING IN ITS NORTH-EAST AND A

WIDE MID-LATITUDES TROUGH COMING FROM THE SOUTH-WEST. UNDER THIS

DOUBLE INFLUENCE, THE PREDICTABILITY OF THE EAST-SOUTH-EASTWARD TRACK

IS QUITE HIGH AND THE MODEL GUIDANCE IS THUS IN AGREEMENT. FROM

THURSDAY EVENING, NONE OF THE AVAILABLE MODELS ALLOW FANTALA TO REACH

THE TROUGH, WHICH IS AN EXIT DOOR TOWARDS THE MID-LATITUDES. A NEW

HIGH GEOPOTENTIAL CELL FOLLOWING THE TROUGH IS FORECASTED TO SETTLE

OVER SOUTH AF MADAGASCAR AND PROGRESSIVELY EXTEND NORTHWARD. FANTALA

SHOULD SLOW AGAIN AND FRIDAY, IT COULD TRACK NORTH-WESTWARD AGAIN,

STEERED BY THIS WIDE RIDGE IN ITS SOUTH-WEST.

THEN , UNTIL THE END OF THE FORECAST PERIOD, THE WEAKENED SYSTEM IS

LIKELY TO BE STEERED BY THE HIGH SUBTROPICAL BELT IN THE LOW AND MID

TROPOSPHERE, AND SHOULD KEEP ON A WEST-NORTH-WESTWARD TO

NORTH-WESTWARD TRACK.



FROM TOMORROW AFTERNOON, IN ADDITION TO THE DEGRADED ENEGERTIC

CONDITIONS, THE UPPER LEVEL ENVIRONMENTAL CONDITIONS SHOULD BECOME

LESS CONDUCIVE WITH A WEAK TO MODERATE NORTHWESTERLY UPPER LEVEL

WINDSHEAR. THUS, FANTALA'S INTENSITY IS LIKELY TO DECREASE UP TO

FRIDAY, AND THEN, REMAIN STEADY OR INTENSIFY SLIGHTLY THANKS TO

BETTER UPPER LEVEL DIVERGENCE.=