South China Sea: Tropical Storm Yagi tracking west-northwestward across the South China Sea as of early Sept. 3 /update 2

Tropical Storm Yagi, known in the Philippines as Enteng, is tracking west-northwestward across the South China Sea early Sept. 3, having made landfall over northern Aurora Province in the Phillippines early Sept. 2 and crossing the country through Sept. 2. As of 11:00 PHT, the system's center of circulation was approximately 441 km (274 miles) north-northwest of Manila.

Forecast models indicate that the storm will strengthen rapidly into a typhoon as it tracks generally westward over the South China Sea through Sept. 5 before making landfall over northeastern Hainan Island early Sept. 6. The system is expected to weaken further but remain a typhoon as it tracks northwestward over the Gulf of Tonkin and make 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 through early Sept. 8. Some uncertainty remains in the track and intensity forecast, and significant changes could occur in the coming days.

As of early Sept. 3, the Philippine Atmospheric, Geophysical and Astronomical Services Administration (PAGASA) has warned of 10-20 cm (4-8 inches) of rainfall over Abra and Ilocos Sur provinces Sept. 3. Lesser rainfall of 5-10 cm (2-4 inches) is forecast over the rest of Ilocos Region as well as Benguet and western Mountain provinces. The enhanced Southwest Monsoon will bring moderate to intense rainfall to other areas of Luzon, especially along the western areas, over the coming days. Forecast rainfall is generally higher in elevated or mountainous areas; flooding and rain-induced landslides are likely, especially in highly susceptible areas and in localities that have experienced considerable amounts of rainfall over the past several days. Tropical cyclone wind signal (TCWS) 2 (on a five-tier scale) remains in place over western Ilocos Norte and northern Ilocos Sur provinces. TCWS 1 is in place for the rest of Ilocos Norte, the rest of Ilocos Sur, northern La Union, Apayao, Kalinga, Abra, western Mountain Province, northern Benguet, and western Cagayan, including Fuga and Dalupiri Islands. Rough seas are also expected across many coastal waters around the Philippines as a result of the storm. Officials will likely update and extend the coverage of the relevant weather alerts over the coming days as the system progresses.

Initial reports indicate at least 13 fatalities across affected areas associated with the passing of the storm. Around 300 families were pre-emptively evacuated in the Tondo area of Metro Manila Sept. 2. Government offices and schools are closed across Calabarzon Region, the National Capital Region, and several other parts of Luzon Sept. 3 due to the severe weather. Dozens of roads remain flooded across parts of Metro Manila and surrounding areas early Sept. 3. Severe flooding is also ongoing in neighboring Rizal Province. Around 300 people in Naga in the Bicol Region and more than 3,600 people in Pasig City in the National Capital Region remain in evacuation shelters due to flooding. At least 67 domestic flights have been canceled due to the storm, and several ferry services have been suspended. Reports indicate that more than 800 people remain stranded at various seaports across the Eastern Visayas, Bicol, and Calabarzon regions, with the Eastern Visayas Region the worst affected. Power outages affected more than 28,000 people in Manila Sept. 2; some power has since been restored.

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.

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