Philippine Sea: Tropical Storm Krathon tracking southwestward in the Philippine Sea Sept. 28 /update 1

Tropical Storm Krathon (named Julian in the Philippines) is tracking southwestward over the Philippine Sea Sept. 28. As of 14:00 PHST, the system's center of circulation was approximately 917 km (570 miles) south-southwest of Kadena Airbase, Okinawa Prefecture, Japan.

Forecast models indicate that the storm will strengthen into a typhoon as it turns to track west-northwestward and then northwestward Sept. 28-30, moving away from Luzon, Philippines. The system is forecast to pass close to the Batanes Islands early Oct. 1 and will strengthen further as it tracks north-northwestward away from the Philippines Oct. 1. The system will then weaken slightly as it tracks northward and then northeastward to the east of Taiwan Oct. 2 and passes close to Yonaguni Island in Japan's Yaeyama Islands early Oct. 3 before moving into the East China Sea. Some uncertainty remains in the track and intensity forecast, and significant changes could occur in the coming days.

As of Sept. 28, the Philippine Atmospheric, Geophysical and Astronomical Services Administration (PAGASA) has issued a weather bulletin advising that the system will bring strong winds to northeastern regions and rough seas to coastal waters. A Tropical Cyclone Warning Signal (TCWS) 1 (the lowest level on a five-tier scale) is in place for Batanes, Cagayan including the Babuyan Islands, eastern and northern Isabela, Apayo, and Ilocos Norte provinces. A separate weather advisory has also been issued for heavy rainfall associated with the storm system across northern regions. Rainfall totals of over 20 cm (8 inches) are expected in the Babuyan Islands Sept. 30 and 10-20 cm (4-8 inches) in the Babuyan Islands Sept. 28, across Cagayan Province Sept. 29, and Batanes, mainland Cagayan, Apayao, Abra, and Ilocos Norte provinces Sept. 30. Rainfall totals of 5-10 cm (2-4 inches) are expected across other northern parts of Luzon over the coming days. Officials will likely update and extend the coverage of the relevant weather alerts over the coming days as the system progresses.

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. 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.