Tropical Cyclone Dana strengthened to the equivalent of a hurricane/typhoon over the northern Bay of Bengal on Wednesday night.  At 5:00 a.m. EDT on Thursday the center of Tropical Cyclone Dana was located at latitude 19.3°N and longitude 87.5°E which put the center about 245 miles (395 km) south of Kolkata, India.  Dana was moving toward the west-northwest at 7 m.p.h. (11 km/h).  The maximum sustained wind speed was 75 m.p.h. (120 km/h) and there were wind gusts to 90 m.p.h. (145 km/h).  The minimum surface pressure was 985 mb.

Tropical Cyclone Dana strengthened to the equivalent of a hurricane/typhoon over the northern Bay of Bengal on Wednesday night.  More thunderstorms formed close to the center of Dana’s circulation.  Bands of showers and thunderstorms were revolving around the center of Tropical Cyclone Dana.  Storms near the center of Dana’s circulation generated more upper level divergence that pumped mass away from the tropical cyclone.  The removal of more mass caused the surface pressure to decrease.

The distribution of wind speeds around Tropical Cyclone Dana was more symmetrical on Thursday morning.  Winds to hurricane/typhoon force extended out 45 miles (75 km) from the center of Dana’s circulation.  Winds to tropical storm force extended out 130 miles (210 km) from the center of Tropical Cyclone Dana.

Tropical Cyclone Dana will move through an environment favorable for intensification during the next 12 hours.  Dana will move over water where the Sea Surface Temperatures are near 30°C.  It will move under the middle of an upper level ridge over the Bay of Bengal.  The upper level winds are weak near the middle of the ridge and there will be little vertical wind shear.   Tropical Cyclone Dana will intensify during the next 12 hours.

Tropical Cyclone Dana will move around the western side of a high pressure system over Southeast Asia.  The high pressure system will steer Dana toward the northwest during the next 24 hours.  On its anticipated track, Tropical Cyclone Dana will reach the coast of India southwest of Kolkata in 12 hours.

Tropical Cyclone Dana will bring strong winds and locally heavy rain to Odisha and West Bengal.  Heavy rain is likely to cause flash floods in some locations.  Dana will also cause a storm surge of up to 7 feet (2 meters) along the coast of Odisha and West Bengal.