WTIO30 FMEE 300631 RSMC / TROPICAL CYCLONE CENTER / LA REUNION TROPICAL CYCLONE FORECAST WARNING (SOUTH-WEST INDIAN OCEAN) 0.A WARNING NUMBER: 13/5/20172018 1.A TROPICAL CYCLONE 5 (CEBILE) 2.A POSITION 2018/01/30 AT 0600 UTC: WITHIN 15 NM RADIUS OF POINT 16.1 S / 79.6 E (SIXTEEN DECIMAL ONE DEGREES SOUTH AND SEVENTY NINE DECIMAL SIX DEGREES EAST) MOVEMENT : WEST 5 KT 3.A DVORAK ANALYSIS: 5.0/5.5/S 0.0/6 H 4.A CENTRAL PRESSURE: 960 HPA 5.A MAX AVERAGE WIND SPEED (10 MN): 80 KT RADIUS OF MAXIMUM WINDS (RMW) :56 KM 6.A EXTENSION OF WIND BY QUADRANTS (KM): 28 KT NE: 210 SE: 370 SW: 370 NW: 190 34 KT NE: 150 SE: 190 SW: 190 NW: 150 48 KT NE: 120 SE: 140 SW: 140 NW: 120 64 KT NE: 80 SE: 90 SW: 90 NW: 80 7.A FIRST CLOSED ISOBAR (PRESSURE / AVERAGE DIAM): 1007 HPA / 1000 KM 8.A VERTICAL EXTENSION OF CYCLONE CIRCULATION : DEEP 1.B FORECASTS: 12H: 2018/01/30 18 UTC: 16.0 S / 78.8 E, MAX WIND=090 KT, INTENSE TROPICAL CYCLONE 24H: 2018/01/31 06 UTC: 15.9 S / 77.9 E, MAX WIND=100 KT, INTENSE TROPICAL CYCLONE 36H: 2018/01/31 18 UTC: 16.0 S / 77.3 E, MAX WIND=110 KT, INTENSE TROPICAL CYCLONE 48H: 2018/02/01 06 UTC: 16.4 S / 76.8 E, MAX WIND=100 KT, INTENSE TROPICAL CYCLONE 60H: 2018/02/01 18 UTC: 16.9 S / 76.3 E, MAX WIND=095 KT, INTENSE TROPICAL CYCLONE 72H: 2018/02/02 06 UTC: 17.5 S / 76.0 E, MAX WIND=085 KT, TROPICAL CYCLONE 2.B LONGER-RANGE OUTLOOK : 96H: 2018/02/03 06 UTC: 18.9 S / 77.7 E, MAX WIND=060 KT, SEVERE TROPICAL STORM 120H: 2018/02/04 06 UTC: 22.1 S / 81.4 E, MAX WIND=050 KT, POST-TROPICAL DEPRESSION 2.C ADDITIONAL INFORMATION: T=5.0 CI=5.5 OVER THE LAST 6 HOURS, THE EYEWALL REPLACEMENT CYCLE CAME TO AN END. A FEW RESIDUAL CIRRUS REMAIN WITHIN CEBILE'S WIDE EYE AND ONLY LOW LEVEL CLOUDS STILL MATERIALIZE THE REMAINS OF YESTERDAY'S SMALL EYE. ALTHOUGH CLOUD TOP HAVE SLIGHTLY WARMED UP BEFORE SUNRISE, CONVECTION HAS STRENGTHENED AGAIN OVER THE LAST HOURS. THIS SUGGEST A NEW INTENSIFICATION PHASE TO COME. CEBILE IS STILL TRACKING WESTWARDS, WITH EVEN A SLIGHT WEST-NORTH-WESTWARD TENDENCY ON THE LAST SAT IMAGES. THE SYSTEM IS CAUGHT BETWEEN A SUBTROPICAL RIDGE IN THE SOUTH-WEST AND THE NEAR-EQUATORIAL RIDGE IN THE NORTH-EAST. THESE TWO SYNOPTIC STRUCTURES ARE DRIVING OPPOSITE STEERING FLOWS. THE AVAILABLE MODELS SUGGEST A SLOW WESTWARD TRACK OVER THE NEXT DAYS, SUGGESTING THAT THE SUBTROPICAL INFLUENCE IS SLIGHTLY STRONGER. FROM THE MIDDLE OF THE WEEK, THE SUBTROPICAL RIDGE IS WEAKENING AND THE NEAR-EQUATORIAL RIDGE BECOMES THE MAIN STEERING FLOW. THIS DRIVES A SHARP SOUTH-EASTWARD TURN FOLLOWED BY A GRADUAL ACCELERATION. AS THE INFLUENCE OF THE TWO RIDGES IS VARYING FROM ONE MODEL TO AN OTHER,THE DISPERSION REMAINS HIGH AROUND THIS TRACK FORECAST, RESULTING IN A HIGHER UNCERTAINTY THAN NORMAL. NOW THAT THE EYEWALL REPLACEMENT CYCLE (ERC) IS OVER, THE SYSTEM SHOULD BEGIN TO REINTENSIFY IN THE NEXT HOURS. UNTIL THURSDAY NIGHT, CEBILE SHOULD TRACK WITHIN QUASI-PERFECT CONDITIONS CONCERNING WIND SHEAR, UPPER DIVERGENCE AND OCEANIC HEAT CONTENT, WHICH IS EVEN INCREASING WEST OF 80E. THE SYSTEM SHOULD THEN FIND ENOUGH ENERGY IN THE OCEAN TO SHIELD ITSELF FROM THE SURROUNDING DRY AIR. HOWEVER, IF THE MOTION IS SLOWER THAN EXPECTED, THE SST COOLING COULD SIGNIFICANTLY DECREASE CEBILE'S INTENSITY. CONSISTENTLY WITH THE SPEED OF THE CURRENT TRACK FORECAST, THE SYSTEM SHOULD REMAIN STRONG OVER THE NEXT DAYS (MODULO THE FLUCTUATIONS LINKED TO EVENTUAL ERCS). FROM FRIDAY, THE UPPER CONDITIONS SHOULD BEGIN TO DETERIORATE AS THE WESTERLY SHEAR IS INCREASING AHEAD OF AN UPPER TROUGH.=