Typhoon Wayne formed over the South China Sea, going on to become one of the longest-lived tropical cyclones in the north-western Pacific, lasting 21 days.

Typhoon Wayne, known in the Philippines as Typhoon Miding, is one of the longest-lived tropical cyclones on record in the north-western Pacific Ocean. The system meandered for 21 days in August–September 1986 between the South China Sea and far western tropical North Pacific Ocean, staying within the monsoon trough and causing heavy rains across the Philippines, Taiwan, southeast China, Hainan Island, and Vietnam. Its maximum sustained winds peaked at category two strength on the Saffir–Simpson scale. Various signals were raised for Hong Kong three times due to Wayne's unusual track. A total of 490 perished, and the storm caused US$399 million in damage.

The South China Sea, also known as the Southeast Asia Sea, is a marginal sea of the Western Pacific Ocean. It is bounded in the north by South China, in the west by the Indochinese Peninsula, in the east by the islands of Taiwan and northwestern Philippines, and in the south by Borneo, eastern Sumatra and the Bangka Belitung Islands, encompassing an area of around 3,500,000 km² (1,400,000 sq mi). It communicates with the East China Sea via the Taiwan Strait, the Philippine Sea via the Luzon Strait, the Sulu Sea via the straits around Palawan, the Java Sea via the Karimata and Bangka Straits and directly with Gulf of Thailand. The Gulf of Tonkin is part of the South China Sea.

A tropical cyclone is a rapidly rotating storm system with a low-pressure area, a closed low-level atmospheric circulation, strong winds, and a spiral arrangement of thunderstorms that produce heavy rain and squalls. Depending on its location and strength, a tropical cyclone is called a hurricane, typhoon, tropical storm, cyclonic storm, tropical depression, or simply cyclone. A hurricane is a strong tropical cyclone that occurs in the Atlantic Ocean or northeastern Pacific Ocean. A typhoon is the same thing which occurs in the northwestern Pacific Ocean. In the Indian Ocean and South Pacific, comparable storms are referred to as "tropical cyclones". In modern times, on average around 80 to 90 named tropical cyclones form each year around the world, over half of which develop hurricane-force winds of 65 kn or more.