Intense Tropical Cyclone Anais (01S) in Southwest Indian Ocean13S 59.9E
On October 12, 2012, the JTWC issued a Tropical Cyclone Formation Alert (TCFA) on a system near the Chagos Islands.
Soon afterwards, RSMC La Réunion designated the system as a tropical disturbance while located roughly 70 nautical miles (130 km) to the west of Diego Garcia. That afternoon, the JTWC upgraded the system into a tropical depression, giving it the designation 01S.
The next day, RSMC La Réunion reported that the system had intensified into a moderate tropical storm and named it Anais. As the day progressed, Anais began a period of quick intensification- being upgraded into a tropical cyclone by RSMC La Réunion and a category one tropical cyclone by the JTWC.
Anais continued to gradually intensify and was upgraded into an intense tropical cyclone by RSMC La Réunion early on October 14. This marked the earliest formation of an intense tropical cyclone in the South-West Indian Ocean.