Philippines: Tropical Storm Ma-on tracking west-northwestward across South China Sea late Aug. 24 /update 5

Event

Tropical Storm Ma-on (known in the Philippines as Florita) is tracking west-northwestward across the South China Sea as of late Aug. 24. Forecast models indicate the storm will continue to move northwest before making landfall the afternoon of Aug. 25 near Jueshanzhen in Guangdong Province, China. The storm had previously made landfall over Maconacon Town in Isabela Province, Philippines, early Aug. 23 and has crossed over the Philippines. As of approximately 21:00 CST, the storm is approximately 172 km (106 miles) south of Hong Kong, China.

Forecast models indicate that the storm will continue its track northwest across the South China Sea, continuing to be a tropical storm as it makes landfall. After making landfall in Guangdong Aug. 25, the storm is forecast to move across southern Guangdong and Guangxi provinces before weakening into a Tropical Depression as it crosses into northern Vietnam. Some uncertainty remains in the track and intensity forecast. Significant changes could occur in the coming days.

The Shenzhen Meteorological Station has issued an orange typhoon warning; orange is the third highest level on a four-tier scale. Zhongshan authorities have also issued an orange typhoon warning. The Hong Kong Observatory has issued a warning for strong storm activity and strong winds; the warning is active through at least 06:00 Aug. 25. Flooding in low-lying areas is possible. Authorities are advising people to stay away from the shoreline.

The Philippine Atmospheric, Geophysical and Astronomical Services Administration (PAGASA) is warning of rains over western areas, including parts of western Luzon. Strong winds are possible over several areas, including Cavite, Metro Manila, and Quezon as well as in Bulacan, Cagayan Valley, Ilocos Region, and Pampanga. A Gale Warning is in effect over Northern and Central Luzon.

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, rendering some bridges or roadways impassable. Flight disruptions at airports in the affected region and temporary port closures are also possible. Raw sewage and other hazardous materials mixed with floodwaters pose a severe health threat. Hong Kong authorities have closed the Hong Kong-Zhuhai-Macau Bridge to shipping. Shenzhen officials will suspend airport operations at Shenzhen Bao'an International Airport (SZX) 03:00-14:00 Aug. 25. Some rail services will also be disrupted in the city through at least Aug. 26.

Advice

Activate contingency plans in areas where officials forecast 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
Philippine Atmospheric Geophysical and Astronomical Services Administration
China Meteorological Administration
Vietnam National Centre for Hydro-Meteorological Forecasting (NCHMF)