The 2006–2007 South-West Indian Ocean cyclone season featured the second-most intense tropical cyclones for a season in the tropical cyclone basin, only behind the 2018–19 season. The basin contains the waters of the Indian Ocean south of the equator and west of 90°E. Météo-France's meteorological office in Réunion (MFR), the official Regional Specialized Meteorological Center for the South-West Indian Ocean, tracked 15 tropical disturbances, of which eleven attained gale-force winds. The season began in October 2006 with a short-lived tropical disturbance, followed by Anita in November, which was the first named storm of the season. Cyclone Bondo was the first of six intense tropical cyclones, which took a rare track through the southern Seychelles before making landfall on northwest Madagascar, killing 11 people. Severe Tropical Storm Clovis lasted from December 2006 to January 2007; it struck eastern Madagascar, killing four people.
In January 2007, Cyclone Dora became one of the two strongest storms of the season, with maximum sustained winds of 195 kilometres per hour (120 miles per hour); Dora only lightly affected the Mauritian island of Rodrigues. The season was most active in February, beginning with Severe Tropical Storm Enok, which formed off eastern Madagascar and later struck the island of St. Brandon. The next storm, Cyclone Favio, tied Dora as the season's strongest storm. Favio took an unusual path south of Madagascar before entering the Mozambique Channel and striking southern Mozambique, killing 10 people and causing widespread flooding. Cyclone Gamede stalled northwest of the Mascarene Islands for a few days in late February, resulting in historic rainfall totals on the French island of Réunion. Over a nine-day period, Gamede dropped 5512 mm (217 in) of rainfall at Commerson Crater, making it one of the wettest tropical cyclones on record. February concluded with Cyclone Humba, which remained over the eastern portion of the basin.
The season's deadliest storm was Cyclone Indlala, which struck northeastern Madagascar on March 15. The cyclone killed 150 people and caused over US$240 million in damage, after resulting in widespread flooding. Less than three weeks after Indlala, Cyclone Jaya struck northeastern Madagascar at a similar location, disrupting ongoing relief efforts and causing one death. The season concluded on April 12, when a subtropical cyclone in the Mozambique Channel transitioned into an extratropical cyclone.
__TOC__
Seasonal forecast and summary
On October 13, 2006, the Mauritius Meteorological Services (MMS) issued their seasonal outlook for the South-west Indian Ocean, anticipating a normal season with about 10 named storms. They forecast El Niño conditions for the southern hemisphere, meaning that normal to slightly above normal activity was likely. They also forecast a weak quasi-biennial oscillation, which would promote cyclone formation in the basin. Other seasonal indicators that were conducive for storm formation included above normal water temperatures, sustained convective activity, and above normal humidity. The seasonal forecast anticipated that most storms would form west of Diego Garcia, with at least one forming in the Mozambique Channel.
Météo-France's meteorological office in Réunion (MFR) – the official Regional Specialized Meteorological Center for the South-West Indian Ocean – tracked all tropical cyclones from the east coast of Africa to 90° E, and south of the equator. Regional warning centers in Mauritius and Madagascar formally named the individual storms. The Joint Typhoon Warning Center (JTWC), which is a joint United States Navy – United States Air Force task force that issues tropical cyclone warnings for the region, also issued advisories for storms during the season.
During the season, the MFR monitored 15 tropical disturbances, including a subtropical cyclone southwest of Madagascar that ended the season in April. There were ten systems that attained the intensity of a moderate tropical storm, which has 10–minute sustained winds of at least ; this is near the long-term average, but much more active than the previous season. There were 58 days in which a tropical storm was active, or five more than the average. Seven of these storms attained tropical cyclone status, which has 10–minute winds of ; the 30 days with a tropical cyclone present was 10 days more than average. Of these cyclones, six strengthened further to an intense tropical cyclone, which has 10 minute winds of . This was the most on record at the time, until it was surpassed by the 2018–19 season. The rest of the southern hemisphere was less active than the Indian Ocean during the 2006–07 cyclone year. The El Niño present at the beginning of the season subsided by January 2007.
Most of the storms in the season occurred in the western portion of the basin. From December 2006 to April 2007, a series of floods and storms affected Madagascar, including Bondo, Clovis, Favio, Gamede, Indlala, and Jaya; this made it the most active season in the country since the 1999–2000 South-West Indian Ocean cyclone season. The series of storms and floods left 10,000 families homeless, directly affecting 9% of the country's population. These floods left 336,470 people in emergency need of food, after the storms destroyed worth of crops. The World Food Programme provided meals, distributed through non-governmental organizations and local officials. This covered the needs for these families until farmers were able to rebuild and regrow their food supply, using seeds provided by the Food and Agriculture Organization. The Malagasy Red Cross provided more than 10,000 residents across the country with insecticide-treated mosquito nets. The series of floods diminished the country's stock of supplies from United Nations agencies, spurring a declaration of a national emergency, and a nearly US$19.5 million appeal for international assistance. Countries around the world donated money or supplies to help the relief effort. UNICEF distributed 100 freezers and refrigerators to health facilities that bore the consequences of the active season. The agency also provided the resources to rebuild or repair 95 schools.
Systems Moderate Tropical Storm Anita
A low-pressure area developed on November 26 to the north of Madagascar. Located within an area of moderate wind shear, the system consolidated its associated convection while moving southwestward. The JTWC classified the system as Tropical Cyclone 03S on November 29. That day, the disturbance turned to the south, paralleling the east coast of Mozambique while moving around a ridge. On November 30, the MFR upgraded the system to Moderate Tropical Storm Anita, estimating peak 10–minute winds of . On the same day, the JTWC estimated peak 1–minute winds of . Anita soon encountered higher wind shear, causing the convection to diminish over the center, and for Anita to weaken back to a tropical depression. The MFR stopped tracking Anita on December 3.
While moving close to Mozambique, Anita dropped heavy rainfall in southeast Tanzania, reaching over 24 hours. Heavy rainfall also occurred in the Comoros, northern Mozambique, and northwest Madagascar, causing flash flooding.
Intense Tropical Cyclone Bondo
A tropical disturbance developed on December 15 in the central Indian Ocean west of Diego Garcia. It strengthened into Moderate Tropical Storm Bondo on December 18. Thereafter, the storm rapidly intensified while moving westward, taking advantage of favorable atmospheric conditions. Within 18 hours of being named, Bondo intensified into tropical cyclone status, or the equivalent of a minimal hurricane. On December 20, the MFR estimated peak 10–minute sustained winds of , although the JTWC estimated stronger 1–minute winds of . While near peak intensity, Bondo passed just south of Agaléga island, before weakening slightly and moving through the Farquhar Group of islands belonging to the Seychelles, becoming the strongest cyclone to affect that island group in decades. Bondo turned southwestward and weakened, followed by re-intensification as it neared the northern tip of Madagascar. Bondo paralleled the coast briefly before it made landfall near Mahajanga on December 25. The storm continued southward, and was last tracked by the MFR on December 28.
Due to its small size, Bondo's winds did not exceed on Agaléga, despite passing close by near peak intensity. In the Seychelles, Bondo severely damaged buildings and vegetation on Providence Atoll. High waves caused flooding elsewhere in the archipelago. In Madagascar, Bondo killed 11 people when it struck the island's west coast. The storm's high winds, reaching in Mahajanga, damaged buildings and left around 20,000 people homeless.
Severe Tropical Storm Clovis
Toward the end of December, the Intertropical Convergence Zone (ITCZ) was active across the southern Indian Ocean. An area of thunderstorms persisted west of Diego Garcia on December 24, which wrapped around a developing circulation. On the next day, the MFR designated the system as Tropical Disturbance 4. The system drifted to the southwest, encountering an area of high wind shear on December 27, causing the circulation to become exposed and weaken. A new, larger circulation developed within the system, prompting the MFR to issue new warnings on Tropical Disturbance 5 on December 29, located southeast of Agaléga. The MFR upgraded the system to Moderate Tropical Storm Clovis on December 31 while the storm was near Tromelin Island. Clovis continued to the south-southwest, steered by a ridge to its southeast. On January 2, the MFR estimated peak 10–minute winds of . The JTWC estimated slightly higher 1–minute winds of , the equivalent of a minimal hurricane. Satellite imagery at this time showed a small eye in the center of the convection. While near peak intensity, Clovis made landfall in eastern Madagascar near Nosy Varika on January 3. The storm rapidly weakened over land while executing a small loop, dissipating on January 4.
High waves affected the north coast of Mauritius. Clovis killed four people in Madagascar, and left 13,465 people homeless. In the country, the storm Clovis dropped heavy rainfall, reaching in Mananjary. The rains caused flooding, which damaged houses, power grids, and crops. At least of rice farms in Mananjary were damaged, representing about 30% of the harvest. Other damaged crops include cassava, banana, vanilla, and fruit trees. The floods left roads impassable in Nosy Varika, which limited communications along with power and phone outages.
Intense Tropical Cyclone Dora