south west indian_ocean cyclone season south west indian_ocean cyclone season average cyclone season named storms tropical cyclones storm attaining maximum sustained winds mph season officially ran november april storms officially tracked france office unofficial basis storm second longest lasting tropical cyclone record basin duration days changed directions times striking southeastern madagascar january considered worst storm cyclone killed people left widespread damage final storm year severe tropical storm significant impact land left million damage usd remaining storms passed near cause impact early february severe tropical storm tropical cyclone active time interacted process effect strongest season originated adjacent australian basin attained peak winds mph open waters indian_ocean march considered stronger april approached northwest coast madagascar dissipated season summary season france office island issued warnings tropical cyclones basin satellite imagery agency estimated intensity dvorak technique warned tropical cyclones region coast africa south equator time recognized later label agency joint united_states navy united_states_air_force task force issued tropical cyclone warnings southwestern indian_ocean season named storms tropical cyclones storm attaining maximum sustained winds mph long term average basin operationally considered tropical cyclone year begin august continue july following year began year july lasted june following year agency tracked short lived tropical cyclones july labeling considered season early storms tropical depression formed east september classified tropical cyclone forming near trough system moved generally southwest dissipating september approached mauritius month tropical cyclone formed closer october classified tropical depression october dropped advisories day system initially drifted south later turned northwest dissipating october final series early tropical systems tropical depression formed east october moved southeastward classified october agency briefly estimated peak winds mph making tropical storm storm looped west dissipated november later precursor australian tropical cyclone tracked eastern portion south west indian_ocean basin middle april classified system minimal tropical storm west classify system entered australian basin april storms named storm season formed december northeast madagascar days southwestward gradually intensifying december intensified tropical cyclone status minute winds mph equivalent minimal hurricane day unofficial warning agency region estimated peak minute winds mph france office estimated minute winds mph drifting days storm began steady southwest motion december greatly weakened system january struck southeastern madagascar near having intensified tropical cyclone status weakened land reaching open waters january storm shifted directions moving generally southward dissipating january second longest lasting tropical cyclone basin start satellite imagery duration days cyclone lasted longer days early duration produced gusty winds moving ashore madagascar cyclone coastal cities heavy rainfall mph wind gusts nearly building damaged destroyed locals considered worst storm region cyclone destroyed large areas crops thousands houses roads bridges killed people left people homeless storm government requested international assistance tropical cyclone tropical disturbance formed january northwest tracked preceding days classified tropical cyclone originated monsoon trough extended low pressure area convergence zone gradually intensified moved slowly southwest high pressure system ridge east january system intensified days later attained tropical cyclone status turning south estimated peak minute winds mph january day estimated peak minute winds mph approaching cold caused weaken storm turned southeastward january system weakened tropical depression status northwest steered ridge southwest day dissipated open waters indian_ocean severe tropical storm january tropical disturbance formed east moving southeastward intensified february day began tracking tropical cyclone quickly intensified upgraded minimal hurricane february minute peak winds mph contrast estimated peak minute winds mph february began interaction located east caused storm turn northwest gradually weakening february storm turned south later southeast weakening tropical depression status day briefly intensified moderate tropical storm february weakened day passing north turning east northeast system turned sharply southward february dissipated day tropical cyclone tropical depression developed monsoon trough february southwest east tracking system days previously classifying tropical cyclone february anticyclone high pressure area system providing favorable conditions depression quickly intensified moving generally south southwestward moderate tropical storm february tropical cyclone day estimated peak minute winds mph assessed stronger minute winds mph time began interaction tropical storm west causing storm turn east southeast increased wind shear weakened cyclone maintained intensity february severe tropical storm quickly fell tropical disturbance status day undergoing loop turning southeast remained weak system days dissipating february began tracking tropical disturbance march mauritius followed days previously classified tropical cyclone day intensified tracking southwestward march upgraded storm equivalent minimal hurricane day followed suit upgrading tropical cyclone status agency estimated peak minute winds mph assessed peak minute intensity mph time storm passed west island accelerated southward gradually weakened influenced approaching trough march storm began transitioning extratropical cyclone completing day extratropical cyclone rapidly intensified influence trough nearby ridge later absorbed moderate tropical storm march tropical depression formed eastern portion basin east southeast nascent quickly intensified storm march day began tracking tropical cyclone moved steadily southwest march turned west northwest followed turn south southwest day time estimated peak minute winds mph assessed peak minute intensity mph turning southward passed east march weakened tropical depression status march dissipated following day having curved southeast intense tropical cyclone march tropical low formed monsoon trough australian basin southwest executed large loop later turned west ridge south named walter march walter crossed south west indian_ocean renamed begin issuing advisories march reached classified system separate number storm existed australian basin moved southwest intensifying tropical cyclone march day upgraded equivalent minimal hurricane day cyclone attained peak winds estimated minute winds mph estimated minute winds mph storm subsequently weakened slowly tropical cyclone status march days later turned southeast weakened tropical depression subjected cooler waters stronger wind shear extratropical days system moved slowly southern indian_ocean turning southwest later southeast dissipating march moderate tropical storm tropical disturbance originated april north originally consisted spiral area thunderstorms gradually organized moved southeastward intensified april passing north day classified tropical cyclone peak minute winds mph agency include advisories contrast estimated peak minute winds mph approached northwest coast madagascar april passing forest turning west ridge south later day system weakened dissipated north madagascar produced mph wind gusts rainfall later gusts reached mph storm dropped precipitation hours severe tropical storm final storm season formed tropical disturbance west southwest moved initially west followed turn south later small loop movement time duration dictated powerful ridge south time system remained weak intensified storm began classifying storm tropical cyclone days prior tropical storm began westward movement gradually curving west northwest bringing north days later storm quickly intensified attain peak minute winds mph severe tropical storm according time stalled drifting slightly west resuming northwest motion influenced ridge south subsequently weakened moving near dissipated low latitude late duration rare storm affect nation passed nearest destroyed island hotel primary island produced strong winds reaching mph international airport strong knock trees nationwide storm caused million usd damage injuries ship passing center reported wind gusts mph
1989–90 South-West Indian Ocean cyclone season