Tropical Cyclone Yaas Strengthens to Equivalent of Hurricane/Typhoon

Tropical Cyclone Yaas strengthened to the equivalent of a hurricane/typhoon over the northern Bay of Bengal on Tuesday. At 11:00 a.m. EDT on Tuesday the center of Tropical Cyclone Yaas was located at latitude 20.1°N and longitude 89.1°E which put it about 195 miles (310 km) south of Kolkata, India. Yaas was moving toward the north at 11 m.p.h. (17 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 972 mb.

Tropical Cyclone Yaas intensified to the equivalent of a hurricane/typhoon south of Kolkata on Tuesday. A broken ring of thunderstorms surrounded the center of Yaas and the strongest winds were occurring in the storms in the ring. Bands of showers and thunderstorms were revolving around the center of Tropical Cylone Yaas. Storms near the center of circulation generated upper level divergence that pumped mass away to the west and north of the tropical cyclone. Winds to hurricane/typhoon force extended out 30 miles (50 km) from the center of Yaas. Winds to tropical storm force extended out 160 miles (260 km) from the center of circulation.

Tropical Cyclone Yaas will move through an environment favorable for intensification during the next 12 hours . Yaas will move over water where the Sea Surface Temperatures are near 30°C. It will move under the southern part of an upper level ridge centered over Bangladesh. The ridge will produce easterly winds which will blow toward the top of the tropical cyclone. Those winds will cause some vertical wind shear, but the shear may not be strong enough to prevent intensification. Tropical Cyclone Yaas could strengthen gradually during the next 12 hours.

Tropical Cyclone Yaas will move around the western side of a high pressure system over Southeast Asia. The high will steer the tropical cyclone toward the north-northwest during the next 36 hours. On its anticipated track Yaas will make landfall on the coastline of Odisha southwest of Kolkata in 15 hours. Tropical Cyclone Yaas will be the equivalent of a hurricane/typhoon when it approaches the coast. Yaas is likely to bring damaging winds and locally heavy rain to the coastal regions of Odisha and West Bengal. Heavy rain could cause flash floods over parts of northeastern India. The coast along the northern Bay of Bengal is very vulnerable to a storm surge. Tropical Cyclone Yaas will cause a dangerous storm surge of up to 9 feet (3 meters) on parts of the coast around the northern Bay of Bengal.