Philippine Sea: Super Typhoon Nanmadol tracking northwestward in the Philippine Sea early Sept. 17 /update 2

Event

Super Typhoon Nanmadol is tracking northwestward over the Philippine Sea early Sept. 17. As of 06:00 JST, the system's center of circulation was approximately 609 km (379 miles) east of Kadena Air Base, Okinawa Prefecture, Japan.

Forecast models indicate that Nanmadol will strengthen briefly over the coming hours before weakening into a typhoon while gradually turning to track northwards and making a close approach to Osumi Islands, Kagoshima Prefecture, Japan, the afternoon of Sept. 18. The storm is then forecast to turn sharply to track northeastward, making landfall as a typhoon over Kumamoto Prefecture, Japan, early Sept. 19. The system will weaken slightly as it tracks northeastward across central Kyushu and exit into the Seto Inland Sea. Subsequent landfalls as a typhoon are forecast over southern Hiroshima and southern Okayama prefectures later the same day. Nanmadol is forecast to weaken into a tropical storm as it tracks northeastward across the northern Kinki, northern Chubu, and southern Tohoku regions before exiting into the North Pacific Ocean near the Fukushima-Miyagi border 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. 17, the Japan Meteorological Agency (JMA) has issued red (middle level on a three-tier scale) high wave warnings across most of Okinawa, Kagoshima, Kochi, eastern Miyazaki, southern Oita, and southern Ehime prefectures. Yellow advisories are in place across the rest of southern and western Japan. 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 40 cm (16 inches) over southern Kyushu, 30 cm (12 inches) in the Tokai and Shikoku regions, and 25 cm (10 inches) in the Amami region. Lesser rainfall amounts are forecast over the rest of western and southern Japan.

As of early Sept. 17, one person remains missing after being washed away from Katsurahama Beach in Kochi City early Sept. 16. Search and rescue operations are being hampered by the large waves.

Authorities will suspend operations on the Kyushu Shinkansen between Kumamoto and Kagoshima-Chuo stations Sept. 18 and between Hakata and Kumamoto from 12:00 the same day. Train services on the Sanyo Shinkansen may be suspended between Hakata and Hiroshima stations and on the Hakata Minami Line from early Sept. 19 depending on weather conditions. Several other local train services across Kyushu, mostly in Kagoshima and Miyazaki prefectures, are suspended Sept. 17. Most train services across southern Kyushu are canceled Sept. 18. Officials at the Fukuoka City Subway have warned that above ground services, especially on the Airport and Hakozaki lines, may be canceled Sept. 18-19.

Japan Airlines (JL) has canceled all flights at New Tanegashima (TNE), Yakushima (KUM), Kikai (KKX), Amami (ASJ), Tokunoshima (TKN), Okinoerabu (OKE), Kitadaito (KTD), and Minami-Daito (MMD) airports Sept. 17 and at Kumamoto (KMJ), Miyazaki (KMI), Kagoshima (KOJ), New Tanegashima (TNE), Yakushima (KUM), Kikai (KKX), Amami (ASJ), Tokunoshima (TKN), and Okinoerabu (OKE) airports Sept. 18. All Nippon Airways (NH) has canceled some flights at Miyazaki (KMI) and Kagoshima (KOJ) airports Sept. 17 and all flights at the airports Sept. 18. Amakusa Airlines (MZ) has canceled all flights from the afternoon of Sept. 17. Additional flight cancelations are likely as the storm approaches and conditions worsen.

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