Typhoon Mitag, known in the Philippines as Typhoon Onyok, was a moderately strong tropical cyclone that severely affected Taiwan, East China and South Korea in early October 2019. The 23rd depression and the 8th typhoon of the 2019 Pacific typhoon season, Mitag developed from a low pressure system near the Micronesia Islands on September 24. Tracking generally northwestward, the system gradually organised and the Japanese Meteorological Agency issued its first advisory on Tropical Depression 19W on September 27. It continued northeastward, gradually organizing and becoming less broad. It was then upgraded to Tropical Storm Mitag on September 28. The storm quickly intensified, becoming a Category 1 typhoon just a day later. It further intensified into a Category 2 typhoon, passing very close to Taiwan. It weakened thereafter, making landfall near Zhoushan in East China on October 1 before weakening back to a poorly organized tropical storm. It later made landfall in South Korea on October 2 before becoming extratropical in the Japan Sea on October 3.