Philippine Sea: Typhoon Koinu tracking westward south of Okinawa, Japan, as of early Oct. 3 /update 1

Event

Typhoon Koinu (known in the Philippines as Jenny) is tracking westward in the Philippine Sea early Oct. 3. As of 05:00 CST, the system's center of circulation is approximately 695 km (432 miles) southeast of Taipei, Taiwan.

Forecast models indicate that the storm will weaken slowly as it tracks west-northwestward across the Philippine Sea through Oct. 4 and make landfall as a typhoon over far southern Taiwan early Oct. 5. Koinu is forecast to weaken further into a tropical storm as it tracks westward across the Taiwan Strait towards Guangdong Province, China, through early Oct. 8. Uncertainty remains in the track and intensity forecast, and significant changes could occur in the coming days.

As of early Oct. 3, the Philippine Atmospheric Geophysical and Astronomical Services Administration (PAGASA) has issued Tropical Cyclone Wind Signal (TCWS) 2 across Batanes Province and TCWS 1 across Cagayan Province, including the Babuyan Islands, and northern and eastern Isabela, Apayao, northeastern Abra, and Ilocos Norte provinces. Rainfall of up to 10 cm (4 inches) is forecast over Batanes and the Babuyan Islands Oct. 3 and up to 20 cm (8 inches) over Batanes Oct. 4.

Taiwan's Central Weather Bureau has issued strong wind advisories over southern, southeastern, and western Taiwan. The Japan Meteorological Agency (JMA) has issued red (middle level on a three-tier scale) high wave warnings over Ishigaki and Miyako islands and yellow thunderstorm and gale advisories across most of the Ryukyu Islands. Authorities will likely issue new warnings or update existing advisories throughout the system's progression in the coming days.

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. 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.

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 (JTWC)
Japan Meteorological Agency (JMA)
Philippine Atmospheric Geophysical and Astronomical Services Administration (PAGASA)
Taiwan Central Weather Bureau
China Meteorological Administration