South China Sea: Tropical Storm Nalgae tracking north-northwest across the South China Sea early Nov. 2 /update 8

Event

Tropical Storm Nalgae is tracking north-northwest across the South China Sea early Nov. 2. As of 11:00 CST, the system's center of circulation was approximately 226 km (140 miles) south-southeast of Hong Kong.

Forecast models indicate that the storm will weaken into a tropical depression before making landfall over the Chuanshan Archipelago in Guangdong Province, China, early Nov. 3. Nalgae is then forecast to track westward off the coast of western Guangdong Province through early Nov. 4, dissipating east of Zhanjiang City. Some uncertainty remains in the track and intensity forecast, and significant changes could occur in the coming days.

As of early Nov. 2, 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 Guangdong Province as well as near the mouth of the Pearl River through the afternoon of Nov. 3. Hong Kong officials have issued Tropical Cyclone Warning Signal No. 3 and Strong Wind Signal No. 3; officials warned that they may issue Typhoon Warning Signal No. 8 the afternoon of Nov. 2. Officials will likely update and extend the coverage of the relevant weather alerts over the coming days as the system progresses. Authorities in Hong Kong have suspended all classes Nov. 2.

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