Tropical Cyclone Roanu intensified on Thursday and it poses an increasing threat to the northern Bay of Bengal. At 11:00 p.m. EDT on Thursday the center of Tropical Cyclone Roanu was located at latitude 17.9°N and longitude 84.9°E which put it about 125 miles (200 km) east of Visakhapatman, India and about 580 miles (935 km) west-southwest of Chittagong, Bangladesh. Roanu was moving toward the north-northeast at 14 m.p.h. (23 km/h). The maximum sustained wind speed was 60 m.p.h. (95 km/h) and there were wind gusts to 70 m.p.h. (115 km/h). The minimum surface pressure was 986 mb.
Most of the thunderstorms in Tropical Cyclone Roanu weakened earlier today and at times it did not look much like a tropical cyclone on satellite imagery. However, a burst of thunderstorm activity near the center of Roanu has occurred in recent hours and an eyelike feature has appeared on conventional satellite imagery. The structure of the circulation improved as a result of the new burst of thunderstorms. The primary rainband now coils more tightly about three quarters of the way around the apparent center of circulation. The thunderstorms near the center of circulation are generating upper level divergence which is pumping out mass in all directions. Several additional bands of thunderstorms have developed over the eastern half of the circulation and Tropical Cyclone Roanu is stronger than it was 24 hours ago.
Tropical Cyclone Roanu is in an environment favorable for intensification. It is over water where the Sea Surface Temperature is near 31°C. Roanu has moved closer to the center of an upper level ridge and the upper levels are not as strong as they were yesterday. As a result the vertical wind shear is much less and the upper level ridge is actually helping to pump mass away from the center of Roanu. The center of the tropical cyclone is near the east coast of India, but the core is expected to remain over water on Friday. Roanu is likely to strengthen further and it could reach hurricane/typhoon intensity.
A ridge east of Roanu is steering the tropical cyclone toward the northeast and that general motion is expected to continue. On its anticipated track Roanu could be south of Kolkata, India in about 18 hours. Tropical Cyclone Roanu could be approaching Chittagong, Bangladesh in 24 to 36 hours.
Tropical Cyclone Roanu poses a significant threat to the northern Bay of Bengal. That area is vulnerable to storm surges. Since Roanu will approach from the southwest, the winds in its counterclockwise circulation will push water toward the north coast of the Bay of Bengal. In addition, a strengthening Tropical Cyclone Roanu will be capable of producing locally heavy rain which could cause inland flooding.