Tag Archives: 98B

Tropical Depression Forms East of Sri Lanka

A Tropical Depression (also designated as Invest 98B) formed over the southern Bay of Bengal east of Sri Lanka on Monday. At 10:00 p.m. EST on Monday the center of a tropical depression was located at latitude 6.7°N and longitude 86.3°E which put it about 295 miles (475 km) east of Pottuvil, Sri Lanka. It was moving toward the west at 7 m.p.h. (11 km/h). The maximum sustained wind speed was 35 m.p.h. (55 km/h) and there were wind gusts to 45 m.p.h. (75 km/h). The minimum surface pressure was 1004 mb.

A low level center of circulation developed in an area of thunderstorms over the southern Bay of Bengal east of Sri Lanka on Monday. The circulation around the tropical depression was still organizing on Monday night. More thunderstorms were developing near the low level center. Bands of showers and thunderstorms were forming outside the center of circulation. Storms near the center started to generate upper level divergence which pumped mass away to the north and west of the tropical depression.

The tropical depression will move through a region somewhat favorable for intensification during the next 24 hours. The depression 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 centered over Southeast Asia. The ridge will produce easterly winds which will blow toward the top of the depression. Those winds will cause moderate vertical wind shear. The shear will inhibit intensification, but it probably will not be strong enough to prevent the tropical depression from intensifying.

The tropical depression will move south of a high pressure system over India and the Bay of Bengal. The high will steer the depression toward the west during the next several days. On its anticipated track the tropical depression will approach Sri Lanka in about 36 hours. It will drop heavy rain over parts of Sri Lanka and flash floods could occur.

Tropical Cyclone Forms Over Northern Bay of Bengal

A tropical cyclone formed over the northern Bay of Bengal on Thursday.  At 11:00 a.m. EDT on Thursday the center of the tropical cyclone was located at latitude 20.0°N and longitude 86.5°E which put it about 25 miles (40 km) south-southwest of Paradip, India.  The cyclone was moving toward the north-northeast at 18 m.p.h. (30 km/h).  The maximum sustained wind speed was 35 m.p.h. (55 km/h) and there were wind gusts to 45 m.p.h. (75 km/h).  The minimum surface pressure was 999 mb.

A center of low pressure developed within a broader area of showers and thunderstorms over the northern Bay of Bengal on Thursday.  A wide band of showers and thunderstorms wrapped around the eastern side of the circulation.  The center of circulation was west of that primary rainband.  Additional bands of showers and thunderstorms formed in other parts of the circulation.  The circulation exhibited enough organization and characteristics to be classified as a tropical cyclone.  The Indian Meteorological Department was giving the the system a classification of depression.

The tropical cyclone is being steered north by a ridge of high pressure to its east.  On its anticipated track the tropical cyclone with make landfall on the coast of the northern Bay of Bengal within 12 hours.  Although the tropical cyclone is moving over water where the Sea Surface Temperature is near 31°C and there is not much vertical wind shear, it does not have much time to intensify before the center moves inland.  The tropical cyclone could strenthen a little more prior to landfall.  It will bring a storm surge of several feet (one to two meters) to the coast along the northern Bay of Bengal.  The tropical cyclone will also drop locally heavy rain and flooding could occur in some parts of India and Bangladesh.