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;
1990–91 South-West Indian Ocean cyclone season
On February 26, a tropical disturbance formed in the northeastern portion of the basin, well to the east-southeast of Diego Garcia. It originated from the monsoon trough, and moved generally to the south-southeast while quickly intensifying. Late on February 26, the MFR upgraded the depression to Tropical Storm Elma, around the same time the JTWC began tracking it as Tropical Cyclone 17S. On February 27, the JTWC estimated Elma attained peak 1‑minute winds of 110 km/h (70 mph), before assessing the storm as weakening. In contrast, the MFR estimated Emla continued to slowly intensify to a 10‑minute peak strength of 105 km/h (65 mph) on March 1. Shortly thereafter, the storm crossed 90° E into the Australian region, where the Bureau of Meteorology estimated that Elma entered at tropical cyclone status. Steady weakening commenced due to the influence of a trough and cooler waters. Elma weakened to the equivalent of tropical depression status by March 3 before turning back to the west. On March 5, the system recrossed 90° E into the south-west Indian Ocean, dissipating shortly thereafter.