The second named storm of the season, Bella originated in the middle of January 1991 from a surge in the monsoon trough to the southwest of Sumatra.

While passing near Rodrigues, Bella produced strong winds and high tides, the latter of which caused flooding in the capital Port Mathurin.

[1][2] On January 13, the Joint Typhoon Warning Center (JTWC)[nb 1] began monitoring a system about 660 km (410 mi) southwest of Padang, Sumatra in the Australian basin.

Moving to the west-southwest, the system crossed into the south-west Indian Ocean on January 17, and the next day was tracked by the Météo France office in Réunion (MFR).

[nb 2] On January 20, the disturbance turned sharply to the south-southeast, although its westward motion resumed late the following day,[5] influenced by a ridge to the south.

[5][2] Following a lengthy period of minimal development, Bella subsequently intensified at a more regular rate as it slowed its forward motion.

[2] On January 28, both the JTWC and the MFR upgraded the storm to the equivalent of a minimal hurricane, estimating winds of 120 km/h (75 mph); this made Bella a tropical cyclone, the first of the season.

[7] While moving near Rodrigues, Bella produced wind gusts of 210 km/h (130 mph),[8] along with high tides that flooded the northern coastline, including the capital Port Mathurin.

[8] Cyclone Bella killed about half of the Rodrigues flying fox, a critically endangered species, decreasing the numbers from around 800 to around 400.

[10] A 16,570 ton cargo ship traveling from Madagascar to Réunion was lost on January 30 about 700 km (430 mi) to the south of the center of Bella.