WTIO30 FMEE 150028 RSMC / TROPICAL CYCLONE CENTER / LA REUNION TROPICAL CYCLONE FORECAST WARNING (SOUTH-WEST INDIAN OCEAN) 0.A WARNING NUMBER: 22/5/20142015 1.A TROPICAL CYCLONE 5 (BANSI) 2.A POSITION 2015/01/15 AT 0000 UTC: WITHIN 10 NM RADIUS OF POINT 17.7 S / 60.2 E (SEVENTEEN DECIMAL SEVEN DEGREES SOUTH AND SIXTY DECIMAL TWO DEGREES EAST) MOVEMENT : EAST-SOUTH-EAST 5 KT 3.A DVORAK ANALYSIS: 5.0/5.0/D 0.5/6 H 4.A CENTRAL PRESSURE: 963 HPA 5.A MAX AVERAGE WIND SPEED (10 MN): 75 KT RADIUS OF MAXIMUM WINDS (RMW) :48 KM 6.A EXTENSION OF WIND BY QUADRANTS (KM): 28 KT NE: 410 SE: 740 SW: 310 NW: 370 34 KT NE: 260 SE: 260 SW: 220 NW: 240 48 KT NE: 120 SE: 120 SW: 120 NW: 120 64 KT NE: 80 SE: 80 SW: 80 NW: 80 7.A FIRST CLOSED ISOBAR (PRESSURE / AVERAGE DIAM): 1004 HPA / 1000 KM 8.A VERTICAL EXTENSION OF CYCLONE CIRCULATION : DEEP 1.B FORECASTS: 12H: 2015/01/15 12 UTC: 18.3 S / 61.7 E, MAX WIND=090 KT, INTENSE TROPICAL CYCLONE 24H: 2015/01/16 00 UTC: 19.1 S / 63.6 E, MAX WIND=090 KT, INTENSE TROPICAL CYCLONE 36H: 2015/01/16 12 UTC: 20.8 S / 65.6 E, MAX WIND=085 KT, TROPICAL CYCLONE 48H: 2015/01/17 00 UTC: 22.4 S / 67.1 E, MAX WIND=080 KT, TROPICAL CYCLONE 60H: 2015/01/17 12 UTC: 23.4 S / 69.0 E, MAX WIND=075 KT, TROPICAL CYCLONE 72H: 2015/01/18 00 UTC: 24.2 S / 71.6 E, MAX WIND=070 KT, POST-TROPICAL DEPRESSION 2.B LONGER-RANGE OUTLOOK : 96H: 2015/01/19 00 UTC: 24.8 S / 75.4 E, MAX WIND=060 KT, POST-TROPICAL DEPRESSION 120H: 2015/01/20 00 UTC: 25.7 S / 78.0 E, MAX WIND=050 KT, POST-TROPICAL DEPRESSION 2.C ADDITIONAL INFORMATIONS: T=5.0- CI=5.0- ANIMATED INFRA RED IMAGERY OVER THE PAST SIX HOURS SHOWS AN IMPROVING LARGE EYE PATTERN. A GOOD POLEWARD OUTFLOW CHANNEL PERSISTS BUT UPPER LEVEL EQUATORWARD DIVERGENCE IS DECREASING. AS FORECASTED, THE TRACK HAS BENT EAST-SOUTH-EASTWARD AND ACCELERATED SLIGHTLY. BANSI IS FORECAST TO ACCELERATE PROGRESSIVELY ON THIS TRACK FOR THE NEXT DAYS, UNDER THE STEERING INFLUENCE OF A NEAR EQUATORIAL RIDGE AND OF A RIDGE BUILDING EASTWARD, IN THE MID TO HIGH LEVELS. THE AVAILABLE NWP MODELS ARE IN TIGHT GOOD AGREEMENT FOR THIS TRACK GENERALLY EAST-SOUTH-EASTWARD AND A SLOWER MOVEMENT AT THE END OF THE FORECAST RANGE. ON THIS TRACK, THE SYSTEM SHOULD KEEP ON WITH FAVORABLE UPPER LEVEL ENVIRONMENT FOR THE NEXT 24 HOURS, WITH LOW VERTICAL WINDSHEAR, AND GOOD POLEWARD OUTFLOW. ON FRIDAY, BANSI SHOULD PROGRESS SOUTH OF THE UPPER LEVEL RIDGE AXIS, AND AN UPPER LEVEL TROUGH SHOULD COME CLOSER THE SYSTEM FROM THE SOUTH-WEST. THE UPPER LEVEL WESTERLY WINDSHEAR SHOULD INCREASE. OWING TO THE LOWERING OF THE OCEANIC HEAT POTENTIAL ON THE SYSTEM TRACK ROUND 25S, BANSI IS LIKELY TO BECOME A POST-TROPICAL HYBRID SYSTEM FROM SATURDAY OR SUNDAY. HOWEVER, THE MAXIMUM WIND SPEED IS LIKELY TO REMAIN STRONG WITHIN THE LOW LEVEL CIRCULATION. ----------------------------------- NUMERICAL STORM SURGE SIMULATIONS : FOR THE SOUTH OF ST-BRANDON ARCHIPELAGO : 0.80 TO 1.30M FOR RODRIGUES ISLAND : 1M50 TO 2M50 NOTE THAT THIS STORM SURGE FORECAST IS TO TAKE WITH CAUTION AND DOES NOT TAKE IN ACCOUNT THE ADDITIONAL SUBMERSION EFFECTS DUE TO THE CYCLONIC SWELL AND THE ASTRONOMIC TIDE. THEREFORE, THE INHABITANTS OF RODRIQUES ISLAND (INCREASING THREAT WITH SEVERE WEATHER CONDITIONS EXPECTED TO SPREAD THURSDAY AND A CLOSEST POINT APPROACH EXPECTED DURING THE NIGHT FROM THURSDAY TO FRIDAY) SHOULD CLOSELY MONITOR THE PROGRESS OF THIS DANGEROUS SYSTEM.=