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Tropical Cyclone Jobo Forms North of Madagascar

Tropical Cyclone Jobo formed just to the north of Madagascar on Tuesday afternoon. At 5:00 p.m. EDT on Tuesday the center of Tropical Cyclone Jobo was located at latitude 10.3°S and longitude 49.8°E which put it about 100 miles (160 km) north of Ansiranana, Madagascar. Jobo was moving toward the west at 13 m.p.h. (20 km/h). The maximum sustained wind speed was 45 m.p.h. (75 km/h) and there were wind gusts to 60 m.p.h. (95 km/h). The minimum surface pressure was 995 mb.

The circulation around a low pressure system north of Madagascar strengthened on Tuesday afternoon and Meteo France la Reunion designated the system as Tropical Cyclone Jobo. The distribution of thunderstorms around Tropical Cyclone Jobo was asymmetrical. Many of the stronger thunderstorms were occurring in bands on the western side of Jobo. Bands on the eastern side of the circulation consisted primarily of showers and lower clouds. The inner end of a rainband was wrapping around the western side of the center of circulation. Storms near the center started to generate upper level divergence that pumped mass away to the north and west of the tropical cyclone. Winds to tropical storm force extended out 85 miles (135 km) from the center of circulation.

Tropical Cyclone Jobo will move through an environment favorable for intensification during the next 36 hours. Jobo will move over water where the Sea Surface Temperatures will be near 29°C. It will move near the northern part of a small upper level ridge. The ridge will produce southeasterly winds which will blow toward the top of the tropical cyclone. Those winds will cause some vertical wind shear. The shear will inhibit intensification, but the wind shear will not be large enough to prevent Tropical Cyclone Jobo from strengthening. Some numerical models are forecasting that Jobo could intensify into the equivalent of a hurricane/typhoon later this week.

Tropical Cyclone Jobo will move north of a surface high pressure system over the Southwest Indian Ocean. The high will steer Jobo slowly toward the west during the next several days. On its anticipated track Tropical Cyclone Jobo will remain north of Madagascar. The steering currents could weaken later this week and Jobo could stall northwest of Madagascar.