Philippine Sea: Typhoon Nanmadol tracking northwestward in the Philippine Sea early Sept. 16 /update 1

Event

Typhoon Nanmadol is tracking northwestward over the Philippine Sea early Sept. 16. As of 12:00 JST, the system's center of circulation was approximately 859 km (534 miles) east-southeast of Kadena Air Base, Okinawa prefecture, Japan.

Forecast models indicate that Nanmadol will strengthen further and make a close approach to Osumi Islands, Kagoshima Prefecture, Japan, early Sept. 18. The storm is then forecast to turn sharply to track northward, making landfall as a typhoon over Kagoshima Prefecture, Japan, late Sept. 18. The system will track northward across western Kyushu through early Sept. 19 before making a sharp turn to track northeastward across northern Kyushu and exit into the Seto Inland Sea. Subsequent landfalls as a typhoon are forecast over southern Yamaguchi and southern Okayama prefectures later the same day. Nanmadol is forecast to weaken as it tracks northeastward across the northern Kinki and northern Chubu regions through early Sept. 21. Some uncertainty remains in the track and intensity forecast, and significant changes could occur in the coming days.

As of early Sept. 16, the Japan Meteorological Agency (JMA) has yet to publish any watches or warnings in relation to the storm. Officials will likely issue relevant weather alerts over the coming days as the system progresses.

The JMA has warned of storms and high waves in the Amami region, Kagoshima Prefecture, as well as landslides and flooding in low-lying and riverine areas across Kyushu and the Amami region. Forecast models indicate heavy rainfall of 20-30 cm (8-12 inches) over Kyushu as well as the Amami and Shikoku regions.

Sustained 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 regional airports and temporary closures of ports are also possible. Raw sewage and other hazardous materials mixed with floodwaters pose a serious health threat.

Advice

Activate contingency plans in areas where officials forecast typhoon or 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
Japan Meteorological Agency
Korea Meteorological Administration