Tropical Cyclone Bulbul Strengthens to Equivalent of Hurricane/Typhoon

Tropical Cyclone Bulbul strengthened into the equivalent of a hurricane/typhoon over the Bay of Bengal on Thursday.  At 4:00 p.m. EST on Thursday the center of Tropical Cyclone Bulbul was located at latitude 16.5°N and longitude 87.5°E which put it about 400 miles (645 km) south of Kolkata, India.  Bulbul was moving toward the 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 976 mb.

The circulation around Tropical Cyclone Bulbul exhibited greater organization on Thursday.  Microwave satellite imagery indicated that an eye was forming at the center of circulation.  A ring of thunderstorms was developing around the eye and the strongest winds were occurring in that ring of storms.  Storms near the center of circulation were generating upper level divergence which was pumping mass away from the tropical cyclone.  Bands of showers and thunderstorms were revolving around the center of Tropical Cyclone Bulbul.  The strongest rainbands were in the northwestern half of Bulbul.  Winds to hurricane/typhoon force extended out 15 miles (25 km) from the center of circulation.  Winds to tropical storm force extended out 145 miles (230 km) from the center.

Tropical Cyclone Bulbul will move through an environment favorable for intensification during the next 24 to 36 hours.  Bulbul will move over water where the Sea Surface Temperature is near 29°C.  It will move under the western end of an upper level ridge over southeast Asia.  The upper level ridge will produce southerly winds which will blow toward the top of the circulation.  There will be southerly winds at all levels and there will not be a lot of vertical wind shear.  Tropical Cyclone Bulbul will intensify during the next 24 to 36 hours.

The ridge over southeast Asia will steer Tropical Cyclone Bulbul toward the north during the next several days.  On its anticipated track Tropical Cyclone Bulbul could approach the area around Kolkata, India in less than 48 hours.  Bulbul could be the equivalent of a hurricane/typhoon when it approaches the coast around the northern end of the Bayof Bengal.