Philippine, Taiwan: Tropical Storm Ma-on tracking westward in the Philippine Sea early Aug. 23 /update 2

Event

Tropical Storm Ma-on (known in the Philippines as Florita) is tracking westward in the Philippine Sea as of early Aug. 23. As of 02:00 PHT, the system's center of circulation was approximately 249 km (155 miles) north-east of Manila, Philippines.

Forecast models indicate that the storm will continue strengthening while turning to track northwestwards, making landfall as a tropical storm near Palanan in Isabela Province, Philippines, early Aug. 23. After landfall, Ma-on will likely continue to strengthen slightly as it tracks northwest over Isabela, Cagayan, Apayao, then Ilocos Norte provinces before exiting into the South China Sea early Aug. 24. The system is likely to strengthen further as it tracks northwestward across the South China Sea, making landfall as a tropical storm over central Guangdong Province, China, just west of Macau, the afternoon of Aug. 25. After landfall, the storm is likely to weaken rapidly and dissipate over eastern Yunnan Province the early Aug. 27. Some uncertainty remains in the track and intensity forecast. Significant changes could occur in the coming days.

The Philippine Atmospheric, Geophysical and Astronomical Services Administration (PAGASA) has warned of moderate to heavy rain, with periods of intense downpours, over most of northern Luzon through late Aug. 24. Tropical Cyclone Wind Signal (TCWS) 3 is in place over the northern and eastern portion of mainland Cagayan and the eastern portion of Isabela province. TCWS 2 is in effect over the rest of Cagayan including the Babuyan Islands, the rest of Isabela, Quirino, the eastern and central portions of Nueva Vizcaya, Ilocos Norte, Ilocos Sur, and the northern and central portions of Aurora. Moderate to rough seas of 1.2-3.1 meters (4-10 feet) are likely over Luzon's northern and eastern seaboards. Officials could update and extend the coverage of the relevant weather alerts over the coming days.

Heavy rainfall could trigger flooding in low-lying areas and those with easily overwhelmed drainage systems. Localized evacuations, flash flooding, and landslides are possible if weather conditions prove hazardous.

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.

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)