Tropical Cyclone Darian weakened over the South Pacific Ocean southeast of Rodrigues on Thursday night. At 10:00 p.m. EST on Thursday the center of Tropical Cyclone Darian was located at latitude 26.6°S and longitude 69.9°E which put it about 635 miles (1025 km) southeast of Rodrigues. Darian was moving toward the southwest at 9 m.p.h. (15 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 994 mb.
A combination of cooler Sea Surface Temperatures and moderate vertical wind shear caused Tropical Cyclone Darian to weaken on Thursday night as it moved over the South Indian Ocean on Thursday night. Darian was moving over water where the Sea Surface Temperatures are near 25˚C. An upper level trough east of Madagascar was producing northwesterly winds that were blowing toward the top of Darian’s circulation. Those winds were causing moderate vertical wind shear. The wind shear and cooler water were also affecting the structure of Tropical Cyclone Darian. Thunderstorms were occurring bands in the southeastern part of Darian’s circulation. Bands in the other parts of Tropical Cyclone Darian consisted primarily of showers and lower clouds. There was still a large circulation around Darian. Winds to tropical storm force extended out 160 miles (260 km) from the center of circulation.
Tropical Cyclone Darian will move through an environment unfavorable for a tropical cyclone during the next few days. Darian will move over water where the Sea Surface Temperatures are colder than 25˚C. The upper level trough east of Madagascar will continue to cause moderate vertical wind shear. Cooler water and moderate vertical wind shear will cause Tropical Cyclone Darian to make a transition to an extratropical cyclone during the next few days. Darian could maintain its intensity while it goes the through the transition to an extratropical cyclone.
The upper level trough east of Madagascar will steer Tropical Cyclone Darian toward the south during the next 48 hours. On its anticipated track, Darian will move farther away from Rodrigues, Mauritius and La Reunion.