Tropical Cyclone Courtney strengthened to the equivalent of a hurricane/typhoon over the South Indian Ocean southeast of the Cocos Islands on Wednesday.  At 5:00 p.m. EDT on Wednesday the center of Tropical Cyclone Courtney was located at latitude 17.3°S and longitude 101.7°E which put the center about 505 miles (815 km) southeast of the Cocos Islands.  Courtney was moving toward the west at 12 m.p.h. (19 km/h).  The maximum sustained wind speed was 80 m.p.h. (130 km/h) and there were wind gusts to 100 m.p.h. (160 km/h).  The minimum surface pressure was 980 mb.

Tropical Cyclone Courtney strengthened steadily on Wednesday.  The inner end of a rainband wrapped around the center of Courtney’s circulation.  Other bands of showers and thunderstorms were revolving around the center of Tropical Storm Courtney.  Storms near the center of Courtney generated upper level divergence that pumped mass away from the tropical cyclone.  The removal of mass caused the surface pressure to decrease.

The size of the circulation around Tropical Cyclone Courtney increased on Wednesday.  Winds to hurricane/typhoon force extended out 30 miles (50 km) from the center of Courtney’s circulation.  Winds to tropical storm force extended out 150 miles (240 km) from the center of Tropical Cyclone Courtney.

Tropical Cyclone Courtney will move through an environment somewhat favorable for intensification during the next 24 hours. Courtney 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 that is west of Australia.  The upper level ridge will produce easterly winds that will blow toward the top of Courtney’s circulation.  Those winds will cause some vertical wind shear.  The vertical wind shear will inhibit intensification, but the wind shear may not be enough to prevent intensification.  Tropical Cyclone Courtney is likely to intensify during the next 24 hours.

Tropical Cyclone Courtney will move around the northern side of a high pressure system that is over the South Indian Ocean.  The high pressure system will steer Courtney toward the west during the next 24 hours.  On its anticipated track, Tropical Cyclone Courtney will pass south of the Cocos Islands later this week.