Philippine Sea: Super Typhoon Usagi tracking northwestward toward the northeastern Philippines as of early Nov. 14 /update 4

Super Typhoon Usagi (known in the Philippines as Ofel) is tracking northwestward in the Philippine Sea toward Luzon in the Philippines early Nov. 14. As of 11:00 PHT, the system's center of circulation was approximately 196 km (122 miles) southeast of Aparri, Philippines.

Forecast models indicate that the system will make landfall over far northeastern Cagayan Province the afternoon of Nov. 14 before tracking northwestward across the Luzon Strait and making another landfall over Fuga Island in the Babuyan Islands later the same day. Usagi is likely to weaken but remain a typhoon as it gradually turns to track northeastward across the Luzon Strait through Nov. 15 and make a close approach to the southern tip of Taiwan early Nov. 16. The storm is then likely to weaken into a tropical storm as it tracks northeastward off the eastern coast of Taiwan through early Nov. 18. Some uncertainty remains in the track and intensity forecast, and changes could occur in the coming days.

As of early Nov. 14, the Philippine Atmospheric, Geophysical and Astronomical Services Administration (PAGASA) has issued a tropical cyclone bulletin advising that the system will bring strong winds and rough seas to northern and central Luzon. There is a moderate to high risk of life-threatening storm surge with peak heights reaching 1-3 meters (0.3-0.9 feet) in the next 48 hours over the low-lying or exposed coastal localities of Batanes, Ilocos Norte, Ilocos Sur, Cagayan including Babuyan Islands, Isabela, and northern Aurora provinces. The following Tropical Cyclone Warning Signals (TCWS) are in place:

• TCWS 5 (the highest level on a five-tier scale): northeastern mainland Cagayan Province.

• TCWS 4: Babuyan Islands, northern and eastern mainland Cagayan, and northeastern Isabela provinces.

• TCWS 3: Batanes, the rest of Cagayan, northern, central, and southeastern Isabela, northern Apayao, and northern Ilocos Norte provinces.

• TCWS 2: western and southern Isabela, northeastern Quirino, the rest of Apayao, Kalinga, northeastern Abra, eastern Mountain Province, eastern Ifugao, the rest of Ilocos Norte, and northern Aurora provinces.

• TCWS 1: the rest of Isabela, the rest of Quirino, Nueva Vizcaya, the rest of Mountain Province, the rest of Ifugao, the rest of Abra, northern Benguet, Ilocos Sur, northern La Union, and northern and central Aurora provinces.

A separate weather advisory for heavy rainfall due to the storm is also in place. Rainfall of more than 20 cm (8 inches) is forecast over Isabela and Cagayan provinces Nov. 14-noon Nov. 15 and Quezon, Camarines Norte, and Camarines Sur provinces Nov. 16-noon Nov. 17. Totals of 10-20 cm (4-8 inches) are forecast over Batanes, Ilocos Norte, Apayao, Kalinga, Mountain Province, Quirino, and Aurora Nov. 14-noon Nov. 15, Batanes, Northern Samar, Eastern Samar, and Sorsogon Nov. 15-noon Nov. 16, and Northern Samar, Albay, Catanduanes, Sorsogon, Marinduque, Cavite, Laguna, Batangas, Rizal, Metro Manila, Pampanga, Bulacan, Bataan, Zambales, Tarlac, Nueva Ecija, and Aurora Nov. 16-noon Nov. 17. Lesser totals of 5-10 cm (2-4 inches) are forecast over other parts of the eastern and northern Philippines Nov. 14-17, with some of the later rainfall associated with the arrival of another storm system named Man-yi.

Authorities have preemptively evacuated tens of thousands of residents in hazardous areas across the Cordillera Administrative, Ilocos, and Cagayan Valley regions. Classes are suspended at schools in parts of Cagayan Valley and Cordillera Administrative regions.

Much of the northern and central Philippines are still recovering from previous storms, including Tropical Storm Trami (named Kristine in the Philippines), which made landfall in Divilacan Town, Isabela Province, at around 00:30 Oct. 24; Tropical Storm Kong-rey (named Leon in the Philippines), which made a close approach to northeastern Luzon Oct. 30-31; Tropical Storm Yinxing (named Marce in the Philippines), which passed over the north coast of Luzon Nov. 7; and Typhoon Toraji (named Nika in the Philippines), which made landfall near Dilasag in Aurora Province early Nov. 11. The succession of tropical systems has caused widespread flooding, damage, and associated disruptions across the region. Tens of thousands of people remain evacuated following damage caused by the storms, with parts of Cagayan Province among the worst affected areas. Further severe weather associated with Super Typhoon Usagi will likely lead to more disruptions and hamper recovery efforts.

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.

Inclement weather could trigger localized business, transport, and utility disruptions, rendering some bridges or roadways impassable. Flight disruptions at regional airports and temporary port closures are also possible. Stagnant pools of water during and after flooding increase insect- and waterborne diseases, such as dengue fever, cholera, and malaria. Exposure to raw sewage and other hazardous materials mixed with floodwaters poses a serious health threat.