Tropical Cyclone Joaninha developed over the Southwest Indian Ocean on Friday. At 5:00 p.m. EDT on Friday the center of Tropical Cyclone Joaninha was located at latitude 15.7°S and longitude 62.2°E which put it about 260 miles (420 km) north-northwest of Rodrigues, Mauritius. Joaninha was moving toward the south at 7 m.p.h. (11 km/h). The maximum sustained wind speed was 50 m.p.h. (80 km/h) and there were wind gusts to 65 m.p.h. (105 km/h). The minimum surface pressure was 992 mb.
More thunderstorms developed near the center of a low pressure system over the Southwest Indian Ocean on Friday and the system was designated Tropical Cyclone Joaninha. The inner end of a band of showers and thunderstorms wrapped around the eastern and southern sides of the center of circulation. However, the distribution of thunderstorms around Joaninha was asymmetrical. Several bands of thunderstorms developed in the eastern half of the circulation. Bands in the western half of the circulation consisted primarily of showers and lower clouds. Thunderstorms near the center were generating upper level divergence which was pumping mass away from the tropical cyclone. Winds to tropical storm force extended out about 150 miles (240 km) from the center of circulation.
Tropical Cyclone Joaninha will move through an environment favorable for intensification during the next several days. Joaninha will move over water where the Sea Surface Temperature is near 29°C. It will move through a region where the upper level winds are weak and there will be little vertical wind shear. Tropical Cyclone Joaninha will continue to intensify during the next 48 to 72 hours. Joaninha could strengthen into the equivalent of a hurricane/typhoon within 24 hours. It could be the equivalent of a major hurricane in 48 to 72 hours.
Tropical Cyclone Joaninha will move around the western end of a ridge of high pressure. The ridge will steer Joaninha toward the south for another day or so. After it rounds the western end of the ridge, Tropical Cyclone Joaninha will move more toward the southeast. On its anticipated track Joaninha could approach Rodrigues in about 72 hours. It could be the equivalent of a major hurricane at that time.