Tropical Cyclone Batsirai Churns Northeast of Mauritius

Tropical Cyclone Batsirai churned northeast of Mauritius on Tuesday morning. At 10:00 a.m. EST on Tuesday the center of Tropical Cyclone Batsirai was located at latitude 17.4°S and longitude 59.7°E which put it about 270 miles (440 km) northeast of Port Louis, Mauritius. Batsirai was moving toward the west-northwest at 11 m.p.h. (17 km/h). The maximum sustained wind speed was 105 m.p.h. (165 km/h) and there were wind gusts to 125 m.p.h. (200 km/h). The minimum surface pressure was 966 mb.

Tropical Cyclone Batsirai intensified slowly over the Southwest Indian Ocean northeast of Mauritius on Tuesday morning. A small circular eye was present at the center of Batsirai’s circulation. The eye was surrounded by a ring of strong thunderstorms and the strongest winds were occurring in that ring of storms. Bands of showers and thunderstorms were revolving around the core of Tropical Cyclone Batsirai. Storms near the core generated upper level divergence that pumped mass away from the tropical cyclone.

The core of Tropical Cyclone Batsirai contracted on Tuesday morning, but the overall size of the circulation increased. Winds to hurricane/typhoon force extended out 35 miles (55 km) from the center of Batsirai. Winds to tropical storm force extended out 145 miles (235 km) from the center of circulation. The Hurricane Intensity Index (HII) for Tropical Cyclone Batsirai was 17.8. The Hurricane Size Index (HSI) was 11.3 and the Hurricane Wind Intensity Size Index (HWISI) was 29.1.

Tropical Cyclone Batsirai will move through an environment favorable for intensification during the next 36 hours. Batsirai will move over water where the Sea Surface Temperatures are near 29˚C. It will move under the northern part of an upper level ridge over the Southwest Indian Ocean. The ridge will produced easterly winds that will blow toward the top of Batsirai’s circulation. Those winds will cause some vertical wind shear and the wind shear could inhibit intensification. Tropical Cyclone Batsirai is likely to intensify during the next 24 hours. Batsirai could strengthen to the equivalent of a major hurricane during the next day or two.

Tropical Cyclone Batsirai will move north of a high pressure system over the South Indian Ocean. The high pressure system will steer Batsirai toward the west-southwest during the next several days. On its anticipated track the center of Tropical Cyclone Batsirai will pass north of Mauritius during the next 24 hours. Although the strongest winds in Batsirai will pass north of Mauritius, it could experience tropical storm force winds and locally heavy rain. Locally heavy rain could cause flash floods in some locations. Tropical Cyclone Batsirai could be north of La Reunion in 36 hours. Batsirai could reach the east coast of Madagascar within 72 hours.