The 2008–09 South-West Indian Ocean cyclone season was a slightly above average event in tropical cyclone formation. It began on November 15, 2008, and officially ended on April 30, 2009, with the exception for Mauritius and the Seychelles, for which it ended on May 15, 2009. These dates conventionally delimit the period of each year when most tropical cyclones form in the basin, which is west of 90°E and south of the Equator. Tropical cyclones in this basin were monitored by the Regional Specialised Meteorological Centre in Réunion.
The 2010–11 South-West Indian Ocean cyclone season was the least active cyclone season on record in the basin, tied with 1982–83, producing only three systems of gale intensity. This was due to cooler than normal water temperatures and the Walker circulation – a broad atmospheric circulation – causing unusually moist conditions in the eastern Indian Ocean and unusually dry conditions in the western Indian Ocean. The basin includes the waters of the ocean south of the equator and west of 90º E to the eastern coast of Africa.
Very Intense Tropical Cyclone Fantala was the most intense tropical cyclone recorded in the South-West Indian Ocean in terms of sustained winds. Part of the 2015–16 cyclone season, Fantala formed on 11 April to the south of Diego Garcia, an island in the central Indian Ocean. With a ridge to the south, the storm moved westward for several days while gaining strength, aided by warm waters and decreasing wind shear. Late on 17 April, the Météo-France office on Réunion (MFR) estimated peak 10-minute winds of 250 km/h (155 mph), making Fantala the strongest tropical cyclone of the basin in terms of 10-minute sustained winds. The Joint Typhoon Warning Center (JTWC) estimated peak 1-minute winds of 285 km/h (180 mph), equivalent to Category 5 intensity on the Saffir-Simpson scale, also the strongest on record in the South-West Indian Ocean, in terms of maximum sustained wind speed. Early on 18 April, Fantala reached its peak intensity, with a minimum central pressure of 910 millibars (27 inHg).
Typhoon Nock-ten, known in the Philippines as Super Typhoon Nina, was the strongest Christmas Day tropical cyclone worldwide in terms of 1-minute sustained winds. Forming as a tropical depression southeast of Yap and strengthening into the twenty-sixth tropical storm of the annual typhoon season on December 21, 2016, Nock-ten intensified into the thirteenth typhoon of the season on December 23. Soon afterwards, the system underwent explosive intensification and became a Category 5-equivalent super typhoon early on December 25. Nock-ten weakened shortly afterwards before making eight landfalls over the Philippines. The typhoon weakened rapidly due to the landfalls as it entered the South China Sea on December 26, turned southwest, and ultimately dissipated on December 28 due to the winter monsoon.
The 2018–19 South-West Indian Ocean cyclone season was the costliest and the most active season ever recorded. Additionally, it is also the deadliest cyclone season recorded in the South-West Indian Ocean, surpassing the 1891–92 season in which the 1892 Mauritius cyclone devastated the island of Mauritius, and is mainly due to Cyclone Idai. The season was an event of the annual cycle of tropical cyclone and subtropical cyclone formation in the South-West Indian Ocean basin. It officially began on 15 November 2018, and ended on 30 April 2019, except for Mauritius and the Seychelles, which it ended on 15 May 2019. These dates conventionally delimit the period of each year when most tropical and subtropical cyclones form in the basin, which is west of 90°E and south of the Equator. Tropical and subtropical cyclones in this basin are monitored by the Regional Specialised Meteorological Centre in Réunion.
Intense Tropical Cyclone Kenneth was the strongest tropical cyclone to make landfall in Mozambique since modern records began. The cyclone also caused significant damage in the Comoro Islands and Tanzania. The fourteenth tropical storm, record-breaking tenth tropical cyclone, and ninth intense tropical cyclone of the 2018–19 South-West Indian Ocean cyclone season, Kenneth formed from a vortex that the Météo-France office on La Réunion (MFR) first mentioned on 17 April. The MFR monitored the system over the next several days, before designating it as Tropical Disturbance 14 on 21 April. The disturbance was located in a favorable environment to the north of Madagascar, which allowed it to strengthen into a tropical depression and later a tropical storm, both on the next day. The storm then began a period of rapid intensification, ultimately peaking as an intense tropical cyclone with 10-minute sustained winds of 215 km/h (134 mph) and a minimum central pressure of 934 hPa. At that time, Kenneth began to undergo an eyewall replacement cycle and weakened slightly, before making landfall later that day as an intense tropical cyclone. As a result of land interaction, Kenneth became disorganised as it made landfall and rapidly degenerated thereafter. The storm then shifted southward, with the MFR cancelling all major warnings for inland cities. Kenneth was reclassified as an overland depression after landfall, with the MFR issuing its warning at midnight UTC on 26 April. Thunderstorm activity developed off the coast of Mozambique on 27 April as the system began drifting northward. Kenneth re-emerged off the coast of northern Mozambique on 28 April, before dissipating on the next day.
The 2019–20 South-West Indian Ocean cyclone season was a slightly above-average season in tropical cyclone and subtropical cyclone formation west of 90°E. The season officially began on 15 November, however, the formation of the first system—Zone of Disturbed Weather 01—occurred on 22 July 2019, well before the official start of the season. This was the earliest start to a season since the 2016–17 season. The season then officially ended on 30 April 2020, with the exception of Mauritius and the Seychelles, for which it officially ended on 15 May 2020. These dates conventionally delimit the period of each year when most tropical and subtropical cyclones form in the basin, which is west of 90°E and south of the Equator. Tropical and subtropical cyclones in this basin are monitored by the Regional Specialized Meteorological Centre in Réunion.
The 2020–21 South-West Indian Ocean cyclone season was an above-average season which produced 12 named storms, with 7 strengthening into tropical cyclones. The season started with the formation of Cyclone Alicia in the extreme northeast section of the basin on 12 November 2020, just before the official start of the season, which marked the third season in a row in which a tropical cyclone formed before the official start of the season. It officially began on 15 November 2020, and ended with the dissipation of Cyclone Jobo on 24 April, 6 days before the official end on 30 April 2021, with the exception of Mauritius and the Seychelles, which officially ended on 15 May 2021. These dates conventionally delimit the period of each year when most tropical and subtropical cyclones form in the basin, which is west of 90°E and south of the Equator. Tropical and subtropical cyclones in this basin are monitored by the Regional Specialised Meteorological Centre in Réunion and unofficially by the Joint Typhoon Warning Center.
Severe Tropical Storm Eliakim was a tropical cyclone that affected Madagascar and killed 21 people in 2018. The seventh tropical depression, sixth tropical storm of the 2017–18 South-West Indian Ocean cyclone season, and fourth tropical cyclone in 2018 to impact Madagascar, Eliakim was first noted as an area of atmospheric convection south-southwest of Diego Garcia on 9 March. Developmental conditions were favorable in its vicinity, and on 14 March, both the Joint Typhoon Warning Center (JTWC) and Météo-France La Réunion (MFR) began issuing warnings on the system, with MFR designating it as Tropical Disturbance 7 and the JTWC giving it the designation 14S. On the next day, MFR upgraded the system to a moderate tropical storm, assigning it the name Eliakim. Eliakim further intensified into a severe tropical storm on 15 March, with the JTWC upgrading it to a Category 1-equivalent cyclone on the Saffir–Simpson scale on 16 March. Eliakim made landfall on Masoala at 07:00 UTC, after which MFR estimated maximum 10-minute sustained winds of 110 km/h (70 mph) within the system. Eliakim weakened into a moderate tropical storm before abruptly turning southwards and re-emerging over water on 17 March. Despite unfavorable conditions, Eliakim re-intensified into a severe tropical storm on 19 March before being downgraded back into a moderate tropical storm 6 hours later. Eliakim transitioned into a post-tropical cyclone on 20 March as it moved away from Madagascar, with the MFR last tracking the system on 22 March.
The 2021–22 South-West Indian Ocean cyclone season had the latest start on record. Despite the late start, it was an above-average season that produced 12 named storms, with five becoming tropical cyclones. The season began on 15 November 2021, and ended on 30 April 2022, with the exception for Mauritius and the Seychelles, for which it ended on 15 May 2022. These dates conventionally delimit the period of each year when most tropical and subtropical cyclones form in the basin, which is west of 90°E and south of the Equator. However, tropical cyclones that form at any time between July 1st, 2021 and June 30th, 2022 will count towards the season total. Tropical and subtropical cyclones in this basin are monitored by the Regional Specialised Meteorological Centre in Réunion and unofficially by the Joint Typhoon Warning Center.
The 2021–22 Australian region cyclone season, despite a very high number of tropical lows forming, was slightly below-average in terms of activity, with ten tropical cyclones forming, two of which intensified further into severe tropical cyclones. The season began from 1 November 2021 and ended on 30 April 2022, but a tropical cyclone could form at any time between 1 July 2021 and 30 June 2022 and would count towards the season total. During the season, tropical cyclones will be officially monitored by one of the three tropical cyclone warning centres (TCWCs) for the region which are operated by the Australian Bureau of Meteorology, National Weather Service of Papua New Guinea and the Indonesian Agency for Meteorology, Climatology and Geophysics. The United States Joint Typhoon Warning Center (JTWC) and other national meteorological services including Météo-France and the Fiji Meteorological Service also monitored the basin during the season.
Severe Tropical Storm Ana was a deadly tropical cyclone that affected the African nations of Madagascar, Malawi and Mozambique and was the fourth-deadliest tropical cyclone in 2022, after the Western Pacific Tropical Storm Megi and Tropical Storm Nalgae, and Atlantic Hurricane Ian. The first named storm of the 2021–22 South-West Indian Ocean cyclone season, Ana developed from an area of convection that was designated as Invest 93S northeast of Madagascar.
Intense Tropical Cyclone Batsirai was a deadly tropical cyclone which heavily impacted Madagascar in February 2022, becoming the strongest tropical cyclone to strike Madagascar since Cyclone Enawo in 2017. It made landfall two weeks after Tropical Storm Ana brought deadly floods to the island country in late January. The second tropical disturbance, the first tropical cyclone, and the first intense tropical cyclone of the 2021–22 South-West Indian Ocean cyclone season, Batsirai originated from a tropical disturbance that was first noted on 24 January 2022. It fluctuated in intensity and became a moderate tropical storm on 27 January 2022, after which it unexpectedly rapidly intensified into an intense tropical cyclone. It then weakened and struggled to intensify through the coming days due to present wind shear and dry air, where it weakened after some time. Afterward, it entered much more favorable conditions, rapidly intensified yet again to a high-end Category 4 cyclone on the Saffir–Simpson scale while moving towards Madagascar. The storm underwent an eyewall replacement cycle the next day, and fluctuated in intensity before making landfall in Madagascar as a Category 3 cyclone, later rapidly weakening due to the mountainous terrain on the island.
The 2022–23 South-West Indian Ocean cyclone season was one of the deadliest South-West Indian cyclone seasons on record, mostly due to Cyclone Freddy. It officially began on 15 November 2022, and ended on 30 April 2023, with the exception for Mauritius and the Seychelles, for which it ended on 15 May 2023. These dates conventionally delimit the period of each year when most tropical and subtropical cyclones form in the basin, which is west of 90°E and south of the Equator. However, tropical cyclones can form year-round, and all tropical cyclones that form between 1 July 2022 and 30 June 2023 will be part of the season. Tropical and subtropical cyclones in this basin are monitored by the Regional Specialised Meteorological Centre in Réunion and unofficially by the Joint Typhoon Warning Center. The season was average in terms of the number of systems that formed, with nine systems becoming at least moderate tropical storms, and six reaching tropical cyclone strength. Activity began early, with the first two systems developing in September and October, and ended late with Fabien in May.
The 2022–23 Australian region cyclone season was the fourth consecutive season to have below-average activity in terms of named storms. The season officially started on 1 November 2022 and finished on 30 April 2023, however, a tropical cyclone could form at any time between 1 July 2022 and 30 June 2023 and would count towards the season total, as Tropical Cyclone 01U proved in July 26. During the season, tropical cyclones were officially monitored by one of the three tropical cyclone warning centres (TCWCs) for the region which are operated by the Australian Bureau of Meteorology, National Weather Service of Papua New Guinea and the Indonesian Agency for Meteorology, Climatology and Geophysics. The United States Joint Typhoon Warning Center (JTWC) and other national meteorological services including Météo-France and the Fiji Meteorological Service also monitored the basin during the season.
Tropical Cyclone Cheneso was a strong tropical cyclone that affected Madagascar in January 2023. The fourth tropical storm and fifth tropical cyclone of the 2022–23 South-West Indian Ocean cyclone season, Cheneso developed out of a zone of disturbed weather status which was first monitored at RSMC La Réunion on 17 January. Despite convection wrapping into the curved band pattern, the system formed into a tropical depression on 18 January. The depression strengthened into Severe Tropical Storm Cheneso on the following day. Cheneso made landfall over northern Madagascar and weakened into an inland depression, before emerging into the Mozambique Channel. Cheneso later strengthened into a tropical cyclone on 25 January. The system continued moving southeast, before transitioning into a post–tropical depression on 29 January.
The 2024–25 South-West Indian Ocean cyclone season is the current annual cycle of tropical cyclone and subtropical cyclone formation in the South-West Indian Ocean. It began on 15 November 2024, and will end on 30 April 2025, with the exception for Mauritius and the Seychelles, for which it will end on 15 May 2025. These dates conventionally delimit the period of each year when most tropical and subtropical cyclones form in the basin, which is west of 90°E and south of the Equator. However, tropical cyclones can form year-round with any cyclone forming between 1 July 2024 and 30 June 2025, such as 01, Ancha, and Bheki, will be part of the season. Tropical and subtropical cyclones in this basin are monitored by the Regional Specialised Meteorological Centre in Réunion and unofficially by the Joint Typhoon Warning Center.
The 2023–24 South-West Indian Ocean cyclone season was an above-average season, including ten named storms, six tropical cyclones and two intense tropical cyclones. Despite its moderate activity, it was the least deadly and destructive season in three years. It is the current event of the annual cycle of tropical and subtropical cyclogenesis. It began on 15 November 2023, and ended on 30 April 2024, with the exception for Mauritius and the Seychelles, where it ended on 15 May 2024. These dates conventionally delimit the period of each year when most tropical and subtropical cyclones form in the basin, which is west of 90°E and south of the Equator. However, tropical cyclones can form year-round, and all tropical cyclones that formed between 1 July 2023 and 30 June 2024 would be part of the season. Tropical and subtropical cyclones in this basin are monitored by the Regional Specialised Meteorological Centre in Réunion and unofficially by the Joint Typhoon Warning Center.
Tropical Cyclone Alvaro was a tropical cyclone that traversed over Madagascar during New Year's Day. The first named storm of the 2023-24 South-West Indian Ocean cyclone season, Alvaro originated as a tropical disturbance at the Mozambique Channel. Being forecasted to develop into a moderate tropical storm, the disturbance was in a favorable environment for intensification. Tracking southeast, the system was upgraded into a tropical depression on December 31. It later intensified into a tropical storm, receiving the name Alvaro. Alvaro continued to move and intensify despite vertical wind shear. On January 1, Alvaro further intensified into a tropical cyclone before making landfall over Morombe District, Madagascar. It weakened back to a tropical depression after passing over the mountainous terrain of the island nation. Alvaro re-entered again to the Indian Ocean and intensified back into a moderate tropical storm. Shortly after reintensification, strong wind shear prevented any further development of the storm. Alvaro later transitioned into a post-tropical depression, being last noted on January 4.
Intense Tropical Cyclone Chido was a compact but very powerful, destructive, and deadly tropical cyclone which impacted Southeast Africa in December 2024. Chido, which means a desire in Shona, was the third named storm and the second intense tropical cyclone of the 2024–25 South-West Indian Ocean cyclone season. It became the strongest tropical cyclone to affect Agaléga since Cyclone Andry in 1983, and the most powerful storm to strike Mayotte in at least 90 years.
