WTIO30 FMEE 280656



RSMC / TROPICAL CYCLONE CENTER / LA REUNION

TROPICAL CYCLONE FORECAST WARNING (SOUTH-WEST INDIAN OCEAN)



0.A WARNING NUMBER: 5/5/20172018

1.A TROPICAL CYCLONE  5  (CEBILE)



2.A POSITION 2018/01/28 AT 0600 UTC:

WITHIN 20 NM RADIUS OF POINT 13.2 S / 84.0 E

(THIRTEEN    DECIMAL TWO   DEGREES SOUTH AND EIGHTY FOUR    DECIMAL

ZERO   DEGREES EAST)

MOVEMENT : SOUTH-SOUTH-WEST 8 KT



3.A DVORAK ANALYSIS: 4.5/4.5/D 2.0/24 H



4.A CENTRAL PRESSURE: 977 HPA

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

RADIUS OF MAXIMUM WINDS (RMW) :19 KM



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

28 KT NE: 150 SE: 150 SW: 150 NW: 190

34 KT NE: 110 SE: 80 SW: 90 NW: 150

48 KT NE: 60 SE: 40 SW: 40 NW: 40

64 KT NE: 30 SE: 30 SW: 30 NW: 30



7.A FIRST CLOSED ISOBAR (PRESSURE / AVERAGE DIAM): 1005 HPA / 700 KM

8.A VERTICAL EXTENSION OF CYCLONE CIRCULATION : DEEP



1.B FORECASTS:

12H: 2018/01/28 18 UTC: 14.4 S / 83.0 E, MAX WIND=080 KT, TROPICAL

CYCLONE

24H: 2018/01/29 06 UTC: 15.5 S / 82.0 E, MAX WIND=095 KT, INTENSE

TROPICAL CYCLONE

36H: 2018/01/29 18 UTC: 16.0 S / 81.3 E, MAX WIND=095 KT, INTENSE

TROPICAL CYCLONE

48H: 2018/01/30 06 UTC: 16.2 S / 80.6 E, MAX WIND=090 KT, INTENSE

TROPICAL CYCLONE

60H: 2018/01/30 18 UTC: 16.2 S / 80.0 E, MAX WIND=085 KT, TROPICAL

CYCLONE

72H: 2018/01/31 06 UTC: 16.2 S / 79.5 E, MAX WIND=080 KT, TROPICAL

CYCLONE



2.B LONGER-RANGE OUTLOOK :

96H: 2018/02/01 06 UTC: 16.7 S / 79.1 E, MAX WIND=070 KT, TROPICAL

CYCLONE

120H: 2018/02/02 06 UTC: 17.5 S / 79.4 E, MAX WIND=050 KT, SEVERE

TROPICAL STORM



2.C ADDITIONAL INFORMATION:

T=CI=4.5



MSG1 HRV IMAGERY HAS SHOWN THE RAPID EVOLUTION FROM A CURVED BAND

PATTERN TO AN EYE PATTERN THAT HAS BEEN REACHED AROUND 0400Z. THE

15-20 NM WIDE EYE IS STILL SOMEWHAT RAGGED CURRENTLY. THE ANALYZED

INTENSITY IS BASED ON RSMC DVORAK ANALYSIS. OTHER DVORAK ESTIMATS

RANGE AT 06Z BETWEEN 57 KT TO 80 KT (10 MIN WINDS). AT 0207Z, THE

SATCON IS AT 78 KT (1 MIN WINDS).



CEBILE TRACKS NOW SOUTH-SOUTH-WESTWARD AND IS PLACED UNDER A WEAK

SHEAR, WHICH IS FAVORABLE TO INTENSIFICATION. UNDER THE INFLUENCE OF

THE REBUILDING RIDGE IN THE EAST, CEBILE IS EXPECTED TO TRACK

SOUTH-WESTWARD, ACCELERATING. THEN THE REINFORCEMENT AND THE

NORTHWARD EXTENSION OF THE RIDGE IN ITS SOUTH-WESTERN PART WILL SLOW

THE MOVEMENT OF CEBILE. IN THE MIDDLE OF NEXT WEEK, THE RIDGE WEAKENS

TO ITS SOUTH-EAST ALONG WITH A BUILDING NEAR EQUATORIAL RIDGE TO ITS

NORTH-EAST ALLOWING THE SYSTEM TO TAKE A TURN SOUTHEASTWARD. HOWEVER

THERE IS ALWAYS A LARGE UNCERTAINTY ABOUT THE TRACK BEYOND MONDAY

MAINLY DU TO THE WIDE VARIABILITY IN THE SPEED OF MOVEMENT AMONG THE

NUMERICAL GUIDANCE, AND ALSO ON THE AREA WHERE THE SYSTEM IS EXPECTED

TO TURN SOUTH-EASTWARD.



ALONG THIS TRACK, THE SYSTEM SHOULD FIRST MAINTAIN INTENSIFICATION AS

THE UPPER LEVEL CONSTRAINT IS WEAK. HOWEVER, CEBILE WILL TRANSIT ON

AREAS WHERE THE OCEANIC POTENTIAL IS LESS. MOREOVER, FROM TUESDAY THE

SURROUNDING MID-LEVEL ENVIRONMENT IS EXPECTED TO BECOME VERY DRY

SPECIALLY OVER THE WESTERN AND NORTHERN SEMI-CIRCLE. CEBILE MAY START

BY THAT TIME A SLOW WEAKENING TREND THAT MAY INCREASE LATER IN THE

FORECAST PERIOD WHERE WESTERLY SHEAR INCREASE. INTERNAL DYNAMICS (EYE

WALL REPLACEMENT CYCLE) MAY ALSO MODULATE THE INTENSITY BUT THIS

MECHANISM HAS VERY LOW PREDICTABILITY (VERY SHORT RANGE)=