South China Sea: Typhoon Nalgae is tracking north-northwest across the South China Sea early Nov. 1 /update 7

Event

Typhoon Nalgae, known in the Philippines as Paeng, is tracking north-northwest across the South China Sea early Nov. 1. The storm previously made landfall over Batangas Province in the Philippines the afternoon of Oct. 29 and earlier landfalls over the southern tip of Catanduanes Island and Camarines Sur Province early Oct. 29. As of 11:00 CST, the system's center of circulation was approximately 407 km (253 miles) south-southeast of Hong Kong.

Forecast models indicate that the storm will weaken into a tropical storm over the coming hours before gradually turning to track northwestward towards southern mainland China. Several landfalls are forecast over western Guangdong Province, China early Nov. 3-4 as the storm weakens into a tropical depression and gradually turns to track southwest. Another landfall is likely over northern Hainan Province, China, late Nov. 4. Some uncertainty remains in the track and intensity forecast, and significant changes could occur in the coming days.

As of early Nov. 1, the Philippine Atmospheric, Geophysical and Astronomical Services Administration (PAGASA) has warned of light to moderate rainfall over Mimaropa and Western Visayas regions as well as Bataan and Zambales provinces through Nov. 1.

The China Meteorological Administration has issued a yellow (second lowest-level on a four-tier scale) typhoon warning; heavy rainfall of 5-9 cm (2-3.5 inches) is forecast over the eastern coast of Fujian and the central and eastern coasts of Guangdong through early Nov. 2. Hong Kong officials have issued a Tropical Cyclone Warning Signal No. 3 and a Strong Wind Signal No. 3.

The Taiwan Central Weather Bureau has issued yellow heavy rain advisories (lowest level on a four-tier scale) over Hualien, Pingtung, Taitung, and Yilan counties as well as Keelung, New Taipei, and Taipei cities. Officials will likely update and extend the coverage of the relevant weather alerts over the coming days as the system progresses.

Authorities in the Philippines declared a state of calamity for Aklan, Capiz, and Quezon provinces as well as Binan City in Laguna Province; authorities are likely to declare additional states of calamity over the coming hours and days. As of early Nov. 1, reports indicate that at least 110 people across the Philippines have died and 33 others are missing due to landslides and flooding. Authorities have pre-emptively evacuated more than 347,000 people from flood-prone areas in Luzon and Visayas. More than 865,000 people remain displaced across 2,728 evacuation centers. Authorities have restored power to most of the affected areas. At least 1,507 houses were destroyed by the storm, and another 5,035 houses were partially damaged.

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. Further 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.

Advice

Activate contingency plans in areas where officials forecast typhoon or tropical storm conditions. Heed any evacuation orders that may be issued. Use extreme caution in low-lying coastal areas and near streams, creeks, and other waterways due to the potential for severe flooding and storm surge. Stockpile water, batteries, and other essentials in advance. Charge battery-powered devices when electricity is available; restrict the use of cellular phones to emergencies only. Power down mobile devices when not in use. Keep important documents and necessary medications in waterproof containers. Observe strict food and water precautions, as municipalities could issue boil water advisories following flooding events. Take precautions against insect- and waterborne diseases in the coming weeks.

Plan accordingly for protracted commercial, transport, and logistics disruptions in areas in the path of the storm, especially if vital infrastructure is damaged. Seek updated information on road conditions before driving or routing shipments through areas where flooding has occurred. Confirm flights before checking out of hotels or driving to the airport; clearing passenger backlogs may take several days in some locations.

Resources

Joint Typhoon Warning Center
China Meteorological Administration
Philippine Atmospheric, Geophysical and Astronomical Services Administration
Taiwan Central Weather Bureau