WTIO30 FMEE 011825



RSMC / TROPICAL CYCLONE CENTER / LA REUNION

TROPICAL CYCLONE FORECAST WARNING (SOUTH-WEST INDIAN OCEAN)



0.A WARNING NUMBER: 23/5/20172018

1.A TROPICAL CYCLONE  5  (CEBILE)



2.A POSITION 2018/02/01 AT 1800 UTC:

WITHIN 20 NM RADIUS OF POINT 16.3 S / 75.9 E

(SIXTEEN    DECIMAL THREE   DEGREES SOUTH AND SEVENTY FIVE    DECIMAL

NINE   DEGREES EAST)

MOVEMENT : SOUTH-SOUTH-WEST 4 KT



3.A DVORAK ANALYSIS: 5.0/5.5/W 0.5/6 H



4.A CENTRAL PRESSURE: 960 HPA

5.A MAX AVERAGE WIND SPEED (10 MN): 85 KT

RADIUS OF MAXIMUM WINDS (RMW) :37 KM



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

28 KT NE: 240 SE: 500 SW: 430 NW: 280

34 KT NE: 170 SE: 240 SW: 240 NW: 190

48 KT NE: 110 SE: 150 SW: 150 NW: 130

64 KT NE: 70 SE: 70 SW: 70 NW: 70



7.A FIRST CLOSED ISOBAR (PRESSURE / AVERAGE DIAM): 1009 HPA / 1000 KM

8.A VERTICAL EXTENSION OF CYCLONE CIRCULATION : DEEP



1.B FORECASTS:

12H: 2018/02/02 06 UTC: 17.1 S / 75.6 E, MAX WIND=080 KT, TROPICAL

CYCLONE

24H: 2018/02/02 18 UTC: 17.8 S / 75.9 E, MAX WIND=075 KT, TROPICAL

CYCLONE

36H: 2018/02/03 06 UTC: 18.2 S / 76.7 E, MAX WIND=070 KT, TROPICAL

CYCLONE

48H: 2018/02/03 18 UTC: 18.8 S / 78.2 E, MAX WIND=060 KT, TROPICAL

CYCLONE

60H: 2018/02/04 06 UTC: 19.8 S / 79.6 E, MAX WIND=055 KT, SEVERE

TROPICAL STORM

72H: 2018/02/04 18 UTC: 20.9 S / 80.8 E, MAX WIND=055 KT, SEVERE

TROPICAL STORM



2.B LONGER-RANGE OUTLOOK :

96H: 2018/02/05 18 UTC: 23.5 S / 81.8 E, MAX WIND=055 KT,

POST-TROPICAL DEPRESSION

120H: 2018/02/06 18 UTC: 26.0 S / 81.7 E, MAX WIND=055 KT,

POST-TROPICAL DEPRESSION



2.C ADDITIONAL INFORMATION:

T=5.0- CI=5.5-



DURING THE LAST 6 HOURS, CEBILE STRUCTURE WAS MOST OF THE TIME AN

ELONGATED EYE. THIS DETERIORATION OF THE CLOUD APTTERN IS APPARENTLY

THE CONSEQUENCE OF A DRY AIR INTRUSION IN THE INNER CORE. 1335Z SSMIS

SWATH SHOW A WEAKNESS IN THE NORTHEN EYEWALL. VERTICAL WIND SHEAR IS

ACCORDING TO CIMSS STILL LOW.



CEBILE KEEPS ON TRACKING SOUTH-SOUTH-WESTWARD, AFTER THE WEAKENING OF

THE SUBTROPICAL RIDGE. BY THE END OF TOMMORROW, UNDER THE INFLUENCE

OF THE NEAR-EQUATORIAL RIDGE, THE SYSTEM WILL PROGRESSIVELY TURN

SOUTHEASTWARD WHILE ACCELERATING A LITTLE. AT LONG RANGE, THE ARRIVAL

OF A TROUGH AT SOUTH IS LIKELY TO ATTRACT CEBILE AND THUS INDUCE A

MORE SOUTHWARD TRACK.



THE ATMOSPHERIC AND OCEANIC CONTEXT START DETERIORATING IN THE NEXT

HOURS. A WEAK WEST-NORTHWESTERLY UPPER CONSTRAINT WILL SET UP

TOMORROW AND THEN INCREASE SIGNIFICANTLY ON SATURDAY WITH THE ROSSBY

WAVE BREAKING, WEST OF THE SYSTEM. CEBILE'S INTENSITY IS FORECAST TO

DECAY, ALL THE MORE IT WILL EVOLVE OVER COOLER SST. ON MONDAY, WITH

AN UPPER ANOMALY IN THE VICINITY, THE BELOW 26 DEGREES SST AND THE

VENTING OF THE UPPER WARM CORE BY DRY ENVIRONMENTAL AIR , CEBILE IS

EXPECTED TO BEGIN ITS EXTRA-TROPICALISATION.=