Cyclone Gamede was among the wettest tropical cyclones on record, dropping more than 5.5 m (18 ft) of rain in a nine-day period on Réunion island in the southwest Indian Ocean. The seventh named storm of the 2006-07 South-West Indian Ocean cyclone season, Gamede formed on February 20 as a tropical depression to the south of Diego Garcia. It tracked generally westward and steadily intensified, passing northwest of Mauritius and Réunion as a broad but moderately intense tropical cyclone. For four days it remained within 400 km (250 mi) of Réunion before accelerating southward, and on March 3 Gamede transitioned into an extratropical cyclone to the south of Madagascar.
Gamede broke rainfall records set by Tropical Cyclone Hyacinthe 27 years earlier for the accumulated totals between three and nine days. The rainfall caused moderate damage in Réunion, and in the southern portion of the island a bridge collapsed due to the storm. Two people each were killed on Mauritius and Réunion. The name ''Gamede'' was submitted to the World Meteorological Organization by South Africa.
== Meteorological history ==
On February 19, an area of convection persisted over a weak, but well-defined low-level circulation about 1130 km (700 mi) southeast of Diego Garcia. It quickly developed banding features, and organized into a tropical disturbance. Located beneath an anticyclone, the system experienced weak vertical wind shear and favorable outflow. With a subtropical ridge to its south, the disturbance tracked quickly westward. Early on February 20, Météo-France (MFR) classified the system as Tropical Depression Ten,〔 and later in the day the Joint Typhoon Warning Center (JTWC) issued a tropical cyclone formation alert as the convection improved significantly in organization. It strengthened further, attaining tropical storm status by 0000 UTC on February 21,〔 and six hours later the MFR named the system ''Gamede'' while it was about 785 km (490 mi) south-southwest of Diego Garcia, or about 995 km (620 mi) northeast of Rodrigues.
After being named, Gamede quickly intensified, and the JTWC classified it with winds of 120 km/h (75 mph) early on February 22. As it turned west-southwestward, an eye feature became evident on satellite imagery, and the JTWC upgraded Gamede to tropical cyclone status, or the equivalence of a minimal hurricane. Subsequently, its intensification rate slowed somewhat, due to restricted outflow.〔 At 0000 UTC on February 23 the MFR upgraded the storm to Tropical Cyclone Gamede, and shortly thereafter it passed over Saint Brandon Island.〔 Subsequently, outflow became better established, and the JTWC unofficially estimated the cyclone attained winds of 185 km/h (115 mph) late on February 23 about 250 km (400 mi) north-northeast of Mauritius island. Initially it was forecast to strengthen further, though slight weakening occurred when a nearby upper-level trough restricted outflow.〔
Cyclone Gamede remained a broad system, and by February 24 it produced winds of near gale force up to 670 km (415 mi) southeast of its center; later in the day, it passed about 300 km (190 mi) north of Réunion, its closest point of approach to the island. For over 90 hours, the cyclone remained within 400 km (250 mi) of the island, resulting in torrential rainfall in the island's mountainous region.〔 Radar imagery on the island indicated Gamede maintained an eye diameter of 60–70 km (37–43 mi). After tracking generally southwestward for several days, a building ridge to its south changed the motion of the cyclone to the west before it became quasi-stationary.〔 Initially, it was predicted to continue westward and strike Madagascar near Toamasina. The cyclone re-intensified while executing a small loop, and late on February 25 Gamede officially attained peak winds of 165 km/h (105 mph) about halfway between Réunion island and the coast of Madagascar; at the time, wind gusts in association with the storm reached 230 km/h (135 mph).〔
The cyclone weakened while remaining nearly stationary, losing most of its deep convection due to upwelling; this is the process in which a stationary storm causes the water temperatures to decrease by bringing the cooler, deeper waters to the surface. It remained nearly stationary until beginning a steady south-southwestward motion late on February 26, a change due to an approaching mid-level trough to its south.〔 On February 28, convection increased around a rebuilding eyewall as it accelerated southward, though on March 1 the cyclone again weakened as wind shear increased and as water temperatures gradually decreased. Gamede weakened to tropical storm status as its center became exposed from the deep convection, and late on March 1 it transitioned into an extratropical cyclone. After completing the transition, the storm became nearly stationary for about two days, during which its winds decreased to below gale force. The remnants of Gamede turned westward and persisted until dissipating on March 6.〔
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