Tropical Cyclone Amphan Develops Quickly Over Bay of Bengal

Tropical Cyclone Amphan developed quickly over the Bay of Bengal on Saturday.  At 5:00 p.m. EDT on Saturday the center of Tropical Cyclone Amphan was located at latitude 11.2°N and longitude 86.3°E which put it about 430 miles (695 km) west of Port Blair.  Amphan was moving toward the north at 8 m.p.h (13 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 992 mb.

The circulation around a low pressure system over the Bay of Bengal organized quickly on Saturday and the Indian Meteorological Department designated the system as Tropical Cyclone Amphan.  Thunderstorms formed around the center of Amphan and recent microwave images suggested that an eye could be forming.  Bands of showers and thunderstorms were revolving around the core of Tropical Cyclone Amphan.  The stronger bands were in the western half of the circulation.  Storms near the core of the circulation were generating strong upper level divergence which was pumping mass away from the tropical cyclone in all directions.  Winds to tropical storm force extended out 100 miles (160 km) from the center of Amphan.

Tropical Cyclone Amphan will move through an environment very favorable for intensification.  Amphan will move over water where the Sea Surface Temperature is near 31°C.  It will move under the axis of an upper level ridge over the Bay of Bengal.  The upper level winds are weak near the axis of the ridge and there will be little vertical wind shear.  Tropical Cyclone Amphan is likely to intensify rapidly during the next 36 hours.  Amphan is likely to strengthen into the equivalent of a hurricane/typhoon within 24 hours and it could become the equivalent of a major hurricane within 36 to 48 hours.

Tropical Cyclone Amphan will move around the eastern end of a high pressure system over southeast Asia.  The high will steer Amphan toward the north during the next several days.  On its anticipated track Tropical Cyclone Amphan could approach the coast of northeast Indian and Bangladesh in 72 hours.  Amphan will likely be the equivalent of a major hurricane when it approaches the coast.  Tropical Cyclone Amphan could generate a catastrophic storm surge along the north coast of the Bay of Bengal.