The final named storm of the 2002–03 South-West Indian Ocean cyclone season, Manou formed on May 2 to the southwest of Diego Garcia.

Manou developed a well-defined eye and reached peak winds only 19 km (12 mi) from the eastern Madagascar coastline.

The storm destroyed large areas of crops and disrupted transportation, including damaging the road between Vatomandry and Brickaville.

In late April, an area of convection persisted southwest of Diego Garcia in the southern Indian Ocean.

Located in an area of weak to moderate wind shear, the convection gradually organized while developing outflow.

On May 8 while approaching Madagascar, Manou developed an eye, and as a result, MFR upgraded it to tropical cyclone status, with 10-minute winds of 120 km/h (75 mph).

At that time, gale-force winds extended over 150 km (93 mi) from the center,[2] and MFR estimated a minimum barometric pressure of 950 mbar (28 inHg).

[4] For about 12 hours, Manou drifted off the eastern coast of Madagascar before turning to the south,[3] moving around a ridge to its east.

[2] Before affecting Madagascar, officials in the country advised residents to evacuate to shelters, although the storm was not expected to be as severe as it was.

[9] The road between Vatomandry and Brickaville was washed out or otherwise blocked by landslides, and the village of Ilaka was isolated after the storm wrecked a bridge.

[7] Due to the damage from Manou, the French Red Cross activated its office in Réunion,[6] providing one ton of medicine.

[12] The Malagasy Red Cross had pre-positioned emergency supplies earlier in the cyclone season, and after Manou struck, the agency distributed a water purification unit, medicine, and tents to the affected areas.