Systems 2012–13 South-West Indian Ocean cyclone season

1 systems

1.1 intense tropical cyclone anais
1.2 tropical disturbance 02
1.3 severe tropical storm boldwin
1.4 intense tropical cyclone claudia
1.5 tropical cyclone dumile
1.6 moderate tropical storm emang
1.7 intense tropical cyclone felleng
1.8 tropical cyclone gino
1.9 tropical cyclone haruna
1.10 tropical cyclone imelda
1.11 moderate tropical storm jamala

systems
intense tropical cyclone anais

on october 12, 2012, jtwc issued tropical cyclone formation alert (tcfa) on system near chagos islands. afterwards, rsmc la réunion designated system tropical disturbance while located 70 nautical miles (130 km) west of diego garcia. afternoon, jtwc upgraded system tropical depression, giving designation 01s. next day, rsmc la réunion reported system had intensified moderate tropical storm , named anais. day progressed, anais began period of quick intensification—being upgraded tropical cyclone rsmc la réunion , category 1 tropical cyclone jtwc. anais continued gradually intensify , upgraded intense tropical cyclone rsmc la réunion on october 14, while upgraded category 3 cyclone jtwc, started form defined eye. late on october 15, started weaken, system s eye started collapse, deep convection remained on low level circulation center, , downgraded category 1 cyclone october 16. on october 17, system weakened tropical storm, , low-level circulation center became totally exposed, convection being displaced south due moderate vertical wind shear north west. day progressed, anais weakened tropical depression. on october 19, remnants of anais made landfall on madagascar associated few burst of thunderstorms, before dissipating completely.

on october 14, anais became earliest intense tropical cyclone in south-west indian ocean.

tropical disturbance 02

on november 8, area of low pressure formed far northeast of la reunion. gradually drifted west , developed low-level circulation center (llcc). on next day, isolated convection developed around system fragmented spiral banding. low drifted southwest , weakened on november 12. low pressure area became disorganized , jtwc stopped tracking later day. on november 15, disturbance regained strength , convective banding around llcc improved , jtwc resumed tracking system. @ same time, rsmc la réunion upgraded low pressure area tropical disturbance. next day, system lost of convection , météo france stopped tracking disturbance, reporting forecast models showed no chance of system restrengthening.

severe tropical storm boldwin

on november 13, cluster of thunderstorms formed off western sumatra. on next couple of days, cluster developed circulation center, , became tropical disturbance, being dubbed invest 96s jtwc. on next couple of days, unfavorable conditions haltered development of system. on november 23, system organized under moderate vertical wind shear, , météo-france started track system tropical disturbance midnight, day, météo-france further upgraded system tropical depression. in hours of november 24, rsmc la reunion further upgraded tropical depression moderate tropical storm mauritus assigning name boldwin. later same day, jtwc started tracking system tropical cyclone 02s winds equivalent tropical storm on sshs, while developed eye-like feature. during afternoon, météo-france further upgraded boldwin severe tropical storm 10-minute sustained winds reaching 100 km/h (65 mph). on november 25, storm encountered strong vertical wind shear , of convection got displaced southeast, partially exposing center. day, boldwin weakened moderate tropical storm. later night, boldwin s llcc became exposed , started weakening rapidly. result, jtwc issued final advisory on system. @ same time, météo-france reported boldwin further weakened tropical depression. finally, during hours of november 26, météo-france issued final warning on boldwin, weakened remnant low, moderate vertical wind shear had torn system apart.

intense tropical cyclone claudia

on 29 november nrl began monitoring disturbance located in australian area of responsibility. disturbance moved south-westwards on following week, strengthening wind shear decreased. on 6 december, jtwc issued tcfa , rsmc la réunion commenced advisories tropical disturbance. disturbance located 900 km (550 miles) se of diego garcia. next day named moderate tropical storm claudia nws mauritius. on december 8, cyclone claudia in south indian ocean , had strengthened rapidly winds on 160 km/h (100 mph). on december 10, well-developed eye observed, diameter of approximately 19 km (12 mi). december 11, claudia s eye had dissipated, , cyclone became more disorganized, wind shear causing elongation east west. claudia moved sea surface temperatures below 80 °f (27 °c), result of western edge of high pressure ridge steering system south. on december 12, high vertical wind shear near 30 knots (55.5 km/h; 34.5 mph) impacted northwestern quadrant of low level circulation center, exposing center, became extratropical on cooler waters. on december 13, system became extratropical, low level circulation center becoming exposed, , convection displaced far south of circulation center strong vertical wind shear.

tropical cyclone dumile

on december 28 low pressure area continued organize, significant increase in convection, located west of anticyclone.

in mauritius, storm produced winds 108 km/h (67 mph) downed trees , power lines. transportation across region several disrupted public transit shut down , many roads blocked debris. in cassis, billboard collapsed , damaged nearby home. 1 person found dead after body washed ashore in flic-en-flac. in addition winds, storm brought heavy rains region, amounting 192.8 mm (7.59 in) in arnaud. overall, damage storm limited in mauritius.

cyclone dumile produced strong winds across réunion island, peaking @ 180 km/h (110 mph), downed numerous trees , power lines, leaving approximately 125,000 residents without electricity. downed wires led death of 1 person after tried remove live wire roof of home. additionally 14 people injured storm. heavy rains affected of island, 834 mm (32.8 in) falling in cirad on 24‑hour span. these rains proved beneficial, restoring reservoirs , replenishing rivers, island experienced below-average rainfall in preceding 2 months. significant agricultural damage took place on island, losses reaching €31 million (us$41.3 million). insured losses estimated @ €3.5 million (us$4.7 million).

moderate tropical storm emang

on december 27 cluster of thunderstorms developed weak low pressure area. december 28, jtwc began tracking system, began make significant increase in deep convection, formative convective banding developing around system. @ time, disturbance located west of upper-level anticyclone , directly beneath subtropical ridge center, in area of light vertical wind shear, 805 km (500 mi) north-northwest of learmonth, australia. on december 30, low-level circulation center became partially exposed, being under moderate strong easterly moving vertical wind shear, while western part of system still had deep, persistent convection. january 17, emang became disorganized , weakened small area of flaring convection. low-level circulation center had become weak , poorly defined, due moderate vertical wind shear.

intense tropical cyclone felleng

on january 18, elongated, poorly organized area of convection associated remnants of tropical storm emang lingered near itcz. january 24, rsmc la réunion reported totally exposed vortex occasional burst of convection persisted 470 miles (760 km) nne of rodrigues, , 580 miles (930 km) sw of diego garcia. @ time not expected strengthen, on 26 january, convective activity improved, deep convection , redeveloped defined, partially exposed low level circulation center due moderate vertical wind shear east, , designated tropical depression. continued strengthen moved west, south-west steadily intensified, reaching intense tropical cyclone strength on 30 january while developing defined eye, deep, intense ring of convective banding forming in eyewall. on january 31 eye became less defined, , started collapse. on february 1 system started become elongated, , weakened severe tropical storm began extratropical transition. february 3, felleng became extratropical, low level circulation center becoming totally exposed , elongated, under vertical wind shear, located west of remnant convection.

although center of cyclone felleng remained offshore, heavy rain storm s outer bands triggered significant flooding in parts of madagascar. flood waters rose rapidly in capital antananarivo, flooding many low-lying homes, several hundred hectares of rice fields. government authorities confirmed @ least 800 people have been affected floods in capital alone. across island, 9 people killed , 1,303 left homeless. total of 162 homes destroyed while 1,803 damaged flood waters, of in vatovavy-fitovinany.

heavy rains , winds associated storm impacted réunion island, 11,200 homes left without power. on course of 3 days, 800 mm (31 in) of rain fell in parts of island, resulting in significant flooding. in plaine des cafres, 512 mm (20.2 in) fell during 24‑hour span.

tropical cyclone gino

on 11 february, rsmc la réunion announced tropical depression had formed 760 mi (1230 km) ese of diego garcia. disturbance had first been noticed several days earlier tropical low in australian aor. upgraded , named moderate tropical storm gino. on 12 february @ 1500 utc, storm s maximum sustained winds 75 knots (86.3 mph/138.9 kph) making storm category 1 hurricane. @ time, gino centered near 17.1 south latitude , 79.5 east longitude, 700 nautical miles (805.5 miles/1,296 km) southeast of diego garcia. gino moved south-southwest @ 10 knots (11.5 mph/18.5 kph), around northwestern edge of subtropical ridge of high pressure.

tropical cyclone haruna

in middle of february, area of convection persisted in mozambique channel. system shifted southward after exiting coast of mozambique , slowed drift in response break in subtropical ridge. subsequently, convection became more pronounced , météo france classified system tropical disturbance on february 18. on february 19, system attained gale-force winds , upgraded moderate tropical storm haruna. structure of haruna continued become more symmetrical large radius of maximum winds, developing ragged eye on february 20. based on improved appearance, mfr upgraded haruna severe tropical storm @ 0000 utc day. 12 hours later, agency upgraded haruna further tropical cyclone status, 10 minute winds of 120 km/h (75 mph). day, approaching trough weakened ridge south, causing cyclone slow , move erratically. mfr assessed haruna reached 10 minute winds of 150 km/h (90 mph) on february 20. @ around 0230 utc on february 22, cyclone made landfall 55 km (35 mi) south of morombe in southwestern madagascar. haruna weakened below cyclone status, , while on land accelerated southeast. @ 1200 utc on february 24, mfr issued last advisory after haruna began losing tropical characteristics, designating subtropical depression. next day, jtwc discontinued advisories on storm, noting haruna dissipating 665 km (415 mi) south-southwest of réunion.

striking southwestern coast of madagascar, cyclone haruna impacted areas not see tropical cyclones. significant damage took place north of toliara around mikea forest. storm brought wind gusts estimated @ 210 km/h (130 mph), resulting in extensive damage. many homes lost roofs , numerous roads blocked debris, isolating communities. several days of heavy rain caused extensive flooding, in morombe approximately 70 percent of city destroyed due flash flooding , dam collapses. in nearby toliara, dozens of people evacuated due dangerous flooding. @ least 24 people killed across southern madagascar , 16 listed missing. in addition, @ least 92 injured , 10,000 left homeless after passage of haruna.

tropical cyclone imelda

on april 3, joint typhoon warning center started tracking area of weak, shallow convection located around low-level circulation center (llcc) near 8.5°s 75.6°e. april 4, system developed flaring convection around consolidating, partially exposed llcc. on april 5, system developed convective bands have further deepened, , wrapped tighter around llcc. later day, rsmc designated system zone of disturbed weather 10.

moderate tropical storm jamala

in middle of may, tropical storm jamala existed in northeastern portion of basin.