South China Sea: Super Typhoon Yagi tracking west-northwestward across the South China Sea as of early Sept. 5 /update 4

Super Typhoon Yagi, known in the Philippines as Enteng, is tracking west-northwestward across the South China Sea early Sept. 5. The storm previously made landfall over northern Aurora Province in the Phillippines early Sept. 2 and crossed the country through Sept. 2. As of 11:00 CST, the system's center of circulation was approximately 509 km (316 miles) southeast of Hong Kong.

Forecast models indicate that the storm will weaken slightly into a typhoon and make landfall over far southwestern Guangdong Province late Sept. 6 before exiting into the Gulf of Tonkin. The system is expected to weaken further but remain a typhoon as it tracks west-northwestward over the Gulf of Tonkin and makes landfall over Quang Ninh Province in northeastern Vietnam late Sept. 7. After landfall, Yagi is likely to weaken rapidly into a tropical storm as it tracks northwestward across northern Vietnam and northern Laos through Sept. 8 before dissipating over far southern Yunnan Province in China early Sept. 9. Some uncertainty remains in the track and intensity forecast, and significant changes could occur in the coming days.

As of early Sept. 5, the China Meteorological Administration has issued a red (the highest level on a four-tier scale) typhoon warning; heavy to torrential rain is likely across the southern coastal area of ​​Guangdong and Hainan provinces, while strong winds are forecast over coastal areas of central and southern Fujian, Guangdong, Hainan, and Guangxi provinces. The heaviest rainfall of 10-15 cm (4-6 inches) is likely over northern Hainan Province.

All flights at Haikou Meilan International Airport (HAK) will be suspended 20:00 Sept. 5-6. Trains and ferries on Hainan Island suspended operations Sept. 5-7, including across the Qiongzhou Strait. Authorities in Hainan have suspended work and schools from Sept. 5. Many other schools across southern China are closed. Beaches and coastal tourist attractions across Hainan Island are closed.

Sustained heavy rainfall could trigger flooding in low-lying areas and those with easily overwhelmed drainage systems. If weather conditions prove hazardous, localized evacuations, flash flooding, and landslides are possible.

Inclement weather could trigger localized business, transport, and utility disruptions, rendering some bridges or roadways impassable. Flight disruptions at regional airports and temporary port closures are also possible. Exposure to raw sewage and other hazardous materials mixed with floodwaters poses a serious health threat.