Cyclone Jokwe - Meteorological History

Meteorological History

In the beginning of the month, an area of convection persisted in association with a broad low-level circulation about 565 km (350 mi) west-southwest of Diego Garcia. The disturbance tracked west-southwestward, and on March 2 the Météo-France (MFR) declared it as a weak depression. Initially in an area of moderate wind shear, the system at first failed to maintain deep convection. Early on March 4, convection increased and organized around the center of circulation, and the MFR classified it as Tropical Depression Twelve, about 270 km (170 mi) southwest of the Agalega Islands. Initially the MFR forecast that the depression would intensify further before striking Madagascar.

The cyclone tracked generally westward along the northern periphery of a ridge. The circulation became better defined, though convection was displaced to the west of the center due to persistent wind shear. Intensification was favored, though, due to warm water temperatures and good outflow. Early on March 5, the Joint Typhoon Warning Center (JTWC) classified the system as Tropical Cyclone 22S. Shortly thereafter, the MFR upgraded the depression to Moderate Tropical Storm Jokwe about 675 km (420 mi) southwest of the Agalega Islands, or about 230 km (140 mi) northeast of the northern tip of Madagascar. At first, the storm was smaller than usual, with gale force winds extending 37 km (23 mi) from the center. Jokwe turned to the west-southwest in response to the development of a trough of low pressure in the Mozambique Channel, and late on March 5 the storm crossed over northern Madagascar. The low-level circulation became disorganized due to land interaction, though its mid and upper-level circulation remained well-organized. Subsequently, the storm encountered more favorable conditions, and an eye developed; Jokwe underwent rapid deepening and intensified to tropical cyclone status, or the equivalence of a minimal hurricane, midday on March 6 off the northwest coast of Madagascar.

Shortly after attaining tropical cyclone status, Jokwe began weakening as its eye disappeared, and it weakened to tropical storm status. The weakening trend was short-lived, and after turning westward the storm re-developed a 13 km (8 mi) eye. Jokwe again underwent rapid intensification as it approached the coast of Mozambique, becoming an intense "midget cyclone" with winds of 175 km/h (110 mph) late on March 7; the MFR explained its rapid intensity changes due to its small size. Excellent upper-level outflow and warm waters contributed to the intensification. At 0000 UTC on March 8, Jokwe attained peak winds of 195 km/h (120 mph) about 75 km (45 mi) east of the Island of Mozambique in Nampula Province; at the same time, its gusts reached about 275 km/h (170 mph). It weakened slightly while paralleling the coastline just offshore, and at 1015 UTC Jokwe made landfall between the Island of Mozambique and Angoche.

Cyclone Jokwe remained over land for about 18 hours before emerging into the Mozambique Channel, weakening quickly to tropical storm status. Upon reaching open waters, convection increased over the center, and late on March 9 Jokwe re-intensified to a tropical cyclone as an eye reappeared on satellite imagery. The cyclone turned to the south-southeast, around the periphery of a ridge to its east. An upper-level low to its south produced good outflow which, in combination with warm waters, allowed Jokwe to re-intensify. Late on March 10, the storm passed about 35 km (21 mi) east of Europa Island, and shortly thereafter the MFR upgraded Jokwe to intense tropical cyclone status with winds of 170 km/h (105 mph). Subsequently, an increase in wind shear caused a steady weakening trend, and by March 12 Jokwe weakened to tropical storm status as its center became partially exposed from the deep convection; at the same time, the storm turned to the southwest.

Later on March 12, thunderstorms reformed over the center, as its movement became nearly stationary due to a ridge to its south and northwest. Early on March 13, it began a steady movement to the northwest, and its organization increased with an eye re-appearing; after briefly re-attaining tropical cyclone status, Jokwe again weakened to tropical storm status due to persistent wind shear. Convection continued to diminish, and on March 14 Jokwe weakened to tropical depression status as the center became almost fully exposed. Early on March 15, the MFR issued its last advisory on the system. The remnants accelerated southeastward and dissipated on March 16 to the southwest of Madagascar.

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