WTIO30 FMEE 030658 RSMC / TROPICAL CYCLONE CENTER / LA REUNION TROPICAL CYCLONE FORECAST WARNING (SOUTH-WEST INDIAN OCEAN) 0.A WARNING NUMBER: 29/5/20172018 1.A TROPICAL CYCLONE 5 (CEBILE) 2.A POSITION 2018/02/03 AT 0600 UTC: WITHIN 20 NM RADIUS OF POINT 18.1 S / 77.0 E (EIGHTEEN DECIMAL ONE DEGREES SOUTH AND SEVENTY SEVEN DECIMAL ZERO DEGREES EAST) MOVEMENT : EAST-SOUTH-EAST 7 KT 3.A DVORAK ANALYSIS: 4.0/5.0/W 0.5/6 H 4.A CENTRAL PRESSURE: 958 HPA 5.A MAX AVERAGE WIND SPEED (10 MN): 75 KT RADIUS OF MAXIMUM WINDS (RMW) :65 KM 6.A EXTENSION OF WIND BY QUADRANTS (KM): 28 KT NE: 300 SE: 390 SW: 330 NW: 240 34 KT NE: 220 SE: 240 SW: 220 NW: 160 48 KT NE: 150 SE: 140 SW: 130 NW: 100 64 KT NE: 100 SE: 100 SW: 100 NW: 80 7.A FIRST CLOSED ISOBAR (PRESSURE / AVERAGE DIAM): 1007 HPA / 800 KM 8.A VERTICAL EXTENSION OF CYCLONE CIRCULATION : DEEP 1.B FORECASTS: 12H: 2018/02/03 18 UTC: 19.0 S / 78.4 E, MAX WIND=065 KT, TROPICAL CYCLONE 24H: 2018/02/04 06 UTC: 20.3 S / 79.6 E, MAX WIND=055 KT, SEVERE TROPICAL STORM 36H: 2018/02/04 18 UTC: 21.6 S / 80.5 E, MAX WIND=050 KT, SEVERE TROPICAL STORM 48H: 2018/02/05 06 UTC: 22.9 S / 81.2 E, MAX WIND=050 KT, POST-TROPICAL DEPRESSION 60H: 2018/02/05 18 UTC: 24.3 S / 81.7 E, MAX WIND=050 KT, POST-TROPICAL DEPRESSION 72H: 2018/02/06 06 UTC: 25.5 S / 81.6 E, MAX WIND=045 KT, POST-TROPICAL DEPRESSION 2.B LONGER-RANGE OUTLOOK : 96H: 2018/02/07 06 UTC: 27.9 S / 81.3 E, MAX WIND=045 KT, POST-TROPICAL DEPRESSION 120H: 2018/02/08 06 UTC: 28.7 S / 80.8 E, MAX WIND=040 KT, POST-TROPICAL DEPRESSION 2.C ADDITIONAL INFORMATION: T=4.0 CI=5.0- (CI 00Z CORRECTED AT 5.0-) CEBILE IS SUFFERING: THE CLOUD PATTERN HAS DETERIORATED WITH AN EYE PATTERN NO MORE EVIDENT ON IR IMAGERY. MW DATA OF THIS MORNING SHOW STRONG DIFFERENCES BETWEEN THE EYE AS SEEN WITH MSG-1 IN IR (MORE TO THE EAST) AND THE LOW LEVEL EYE SEEN ON 37 GHZ IMAGERY. THE DIFFERENCE SEEMS TO GO BEYOND THE PARALLAX ASSOCIATED WITH MSG-1 AND IS PROBABLY DUE TO AN INCREASE IN THE WESTERLY CONSTRAINT. DRY ENVIRONMENTAL AIR WILL ALSO HELP TO ENHANCE THE WEAKENING TREND WITHIN THE NEXT 12 HOURS. THE INTENSITY ASSESSMENT AT 75 KT IS IN GOOD AGREEMENT WITH THE LATEST CONSENSUS OF OBJECTIVE ESTIMATES AT 0349Z NEAR 80 KT (10 MIN WINDS). MW OF THIS MORNING WAS ALSO USEFUL TO RELOCATE THE CENTER NORTHWARD AND TO ASSESS A SLOW EAST-SOUTH-EASTWARD MOTION. THIS MOTION SHOULD GRADUALLY BEND SOUTHEASTWARD WITHIN THE NEXT 24 HOURS. FROM MONDAY, THE ARRIVAL OF A TROUGH AT SOUTH ALLOWS TO SHIFT TOWARD THE EAST THE HIGH PRESSURES AND THUS REORIENTED THE CEBILE'S TRACK FURTHER SOUTHWARD BUT WITHOUT REAL ACCELERATION. THE REBUILT OF THE SOUTHERN RIDGE COULD, HOWEVER, DISTURB THIS PROGRESSION SOUTHWARD FROM THURSDAY AS SUGGESTED BY THE ECMWF ENSEMBLE FORECAST. THE ATMOSPHERIC AND OCEANIC CONTEXT IS NOT FAVORABLE TO MAINTAIN THE INTENSITY FOR THE CEBILE CYCLONE. ROSSBY WAVE BREAKING TO THE WEST OF THE SYSTEM ALLOWS A WEST-NORTHWESTERLY UPPER CONSTRAINT. CEBILE'S INTENSITY IS FORECAST TO DECAY, ALL THE MORE IT WILL EVOLVE OVER COOLER SST, AND WILL CONTINUE THIS WEAKENING BEFORE STARTING ITS POST-TROPICAL TRANSITION EARLY NEWT WEEK WITH THE STRONGEST WINDS IN THE SOUTHERN QUADRANT, FAR FROM THE CENTER.=