Tropical Cyclone Vince intensified to the equivalent of a Category 4 hurricane on the Saffir-Simpson Scale over the South Indian Ocean far to the south-southeast of Diego Garcia on Thursday.  At 4:00 p.m. EST on Thursday the center of Tropical Cyclone Vince was located at latitude 19.8°S and longitude 80.2°E which put the center about 985 miles (1590 km) south-southeast of Diego Garcia.  Vince was moving toward the west-southwest at 12 m.p.h. (19 km/h).  The maximum sustained wind speed was 155 m.p.h. (250 km/h) and there were wind gusts to 190 m.p.h. (305 km/h).  The minimum surface pressure was 924 mb.

Tropical Cyclone Vince intensified to the equivalent of a Category 4 hurricane on Thursday.  A circular eye with a diameter of 17 miles (28 km) was at the center of Vince’s circulation.  The eye was surrounded by a ring of strong thunderstorms and the strongest winds were occurring in that ring of storms.  Storms near the center of Vince generated strong upper level divergence that pumped large quantities of mass away from the tropical cyclone in all directions.  The removal of large amounts of mass caused the surface pressure to decrease rapidly,

The size of the circulation around Tropical Cyclone Vince decreased when Vince intensified on Thursday.  Winds to hurricane/typhoon force extended out 45 miles (75 km) from the center of Vince’s circulation.  Winds to tropical storm force extended out 110 miles (175 km) from the center of Tropical Cyclone Vince.

The Hurricane Intensity Index (HII) for Tropical Cyclone Vince is 33.3.  The Hurricane Size Index (HSI) is 16.0 and the Hurricane Wind Intensity Size Index (HWISI) is 49.3.  Tropical Cyclone Vince is similar in size and intensity to Hurricane Ian when Ian hit Southwest Florida in 2022.

Tropical Cyclone Vince will move through an environment favorable for an intense tropical cyclone during the next 24 hours.  Vince will move over water where where the Sea Surface Temperatures are near 28°C.  It will move under the northern part of an upper level ridge over the South Indian Ocean.  The upper level ridge will produce easterly winds that will blow toward the top of Vince’s circulation.  Those winds will cause some vertical wind shear.  The vertical wind shear will inhibit intensification, but the shear will not be enough to prevent intensification.  Tropical Cyclone Vince could intensify during the next 24 hours, unless an eyewall replacement cycle occurs.

Tropical Cyclone Vince will move around the northern side of a high pressure system over the South Indian Ocean.  The high pressure system will steer Vince toward the west-southwest during the next 24 hours.  On its anticipated track Tropical Cyclone Vince will pass far to the south of Diego Garcia.

Elsewhere, Tropical Cyclone Taliah continued to spin east-southeast of the Cocos Islands.  At 4:00 p.m. EST on Thursday the center of Tropical Cyclone Taliah was located at latitude 14.5°S and longitude 101.0°E which put the center about 345 miles (500 km) east-southeast of the Cocos Islands.  Taliah was moving toward the west at 12 m.p.h. (19 km/h).  The maximum sustained wind speed was 70 m.p.h. (110 km/h) and there were wind gusts to 85 m.p.h. (135 km/h).  The minimum surface pressure was 984 mb.