The storm slowly drifted to the west. It got stronger slowyl. Nalgae developed a microwave eye like feature and well defined convective banding in all the quadrants. The system had a tiny radius of winds. It was still strengthening significantly and was very well defined. On the evening of September 28, the JMA reported that Nalgae continued to intensify. They upgraded it to a severe tropical storm with winds of over . On that night, the PAGASA began advisories on Nalgae. They gave it the local name "Quiel" as it entered the Philippine Area of Responsibility (PAR). Late on September 29, the JMA upgraded Nalgae to a typhoon. Nalgae quickly intensified on September 30, and became a category 4 super typhoon early on October 1. This was just before making landfall over Luzon. Due to land interaction and colder sea surface temperature in the South China Sea, the JMA downgraded Nalgae to a severe tropical storm on October 2. Then a tropical storm late on October 3. The JTWC downgraded Nalgae to a tropical depression on October 4. The JMA also did it on the next day. Later on October 5, the last low of Nalgae dissipated.