 That day, a circulation formed in the interaction between the Mid-Pacific trough and an easterly wave, with energy from a surge in the Easterlies in the Southern Hemisphere.Initially winds were very weak, and it tracked west-northwestward while slowly gaining intensity.The official track from the Japan Meteorological Agency (JMA) indicated the system first developed into a tropical cyclone on August 25, whereas the Joint Typhoon Warning Center (JTWC) initiated advisories two days later, after it was observed by the Hurricane Hunters.