Tropical Cyclone Biparjoy Moves Slowly North over Arabian Sea

Tropical Cyclone Biparjoy moved slowly toward the north over the Arabian Sea on Friday morning. At 5:00 a.m. EDT on Friday the center of Tropical Cyclone Biparjoy was located at latitude 15.3°N and longitude 66.9°E which put it about 640 miles (1035 km) south of Karachi, Pakistan. Biparjoy was moving toward the north-northeast at 5 m.p.h. (8 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 987 mb.

The distribution of thunderstorms around Tropical Cyclone Biparjoy was asymmetrical on Friday morning. Many of the thunderstorms were occurring near the center of Biparjoy and in bands in the southern half of the tropical cyclone. bands in the northern half of Biparjoy’s circulation consisted primarily of showers and lower clouds. There appeared to be some drier air in the northern side of Tropical Cyclone Biparjoy. The drier air was inhibiting the formation of thunderstorms in that part of Biparjoy. Storms near the center of Biparjoy’s circulation generated upper level divergence that pumped mass away to the west of the tropical cyclone. Winds to hurricane/typhoon force extended out 20 miles (30 km) from the center of Tropical Cyclone Biparjoy. Winds to tropical storm force extended out 125 miles (200 km) from the center of circulation.

Tropical Cyclone Biparjoy will move through an environment mostly favorable for intensification during the next 24 hours. Biparjoy will move over water where the Sea Surface Temperatures are near 31˚C. It will move under the axis of an upper level ridge over the Arabian Sea. The upper level winds are weak near the axis of the ridge and there will be little vertical wind shear. However, drier air in the northern side of Tropical Cyclone Biparjoy will continue to inhibit formation of thunderstorms in the that part of the circulation. In addition, Biparjoy has been moving slowly and the wind could mix cooler water to the surface of the Arabian Sea. Tropical Cyclone Biparjoy could strengthen during the next 24 hours unless the mixing of cooler water to the surface lowers the Sea Surface Temperature under the core of the circulation.

Tropical Cyclone Biparjoy will move around the northwestern side of a high pressure system over India during the next 24 hours. The high pressure system will steer Biparjoy slowly toward the north. On its anticipated track, Tropical Cyclone Biparjoy will remain over the Arabian Sea during the next few days.