1999–2000 South-West Indian Ocean cyclone season
The 1999–2000 South-West Indian Ocean tropical cyclone season was the first on record in which two storms – Leon–Eline and Hudah – struck Mozambique at tropical cyclone intensity, or with maximum sustained winds of at least 120 km/h (75 mph). The most notable storm of the season was Eline, which was the longest-lasting storm on record in the basin. It lasted for 29 days while traversing the southern Indian Ocean, making the strongest landfall in decades along eastern Madagascar in late February. The storm was the first in a series of three storms that struck the country in early 2000, along with Gloria in March and Hudah in April. Collectively, the three storms killed at least 316 people. The season started on November 1, 1999, and ended for most of the basin on April 30, 2000; for Mauritius and the Seychelles, the season continued until May 15. These dates conventionally delimit the period of each year when most tropical cyclones form in the basin;
1999–2000 South-West Indian Ocean cyclone season
While Eline was making landfall on Madagascar, another area of convection formed to its east on February 17 within the ITCZ. Its structure was similar to a monsoon depression, due to a large circulation with weak winds near the center. However, it was organized enough to be classified as a tropical disturbance on February 18 to the southeast of Diego Garcia. It moved southeastward with increasing convection, prompting the Mauritius Meteorological Service to name it Felicia while still as a tropical depression on February 20. The convection however remained disorganized, and there were several small circulations within the broad gyre. After turning to the southwest due to a nearby trough, Felicia's circulation became more compact, as evidenced by a QuikSCAT pass. Outflow increased as wind shear decreased, and Felicia became a moderate tropical storm on February 21. On the same day, the JTWC initiated advisories on the storm as Tropical Cyclone 12S.