Philippine Sea: Tropical Storm Yun-yeung tracking northward south of Japan as of the morning of Sept. 8 /update 4

Event

Tropical Storm Yun-yeung is tracking northward in the Philippine Sea the morning of Sept. 8. As of 09:00 JST, the system's center of circulation was approximately 383 km (238 miles) southwest of Yokosuka, Kanagawa Prefecture.

Forecast models indicate that the weather system will maintain tropical storm strength as it tracks northward over the Philippine Sea toward Japan through the afternoon of Sept. 8. Yun-yueng will likely make landfall over southeastern Aichi Prefecture the evening of Sept. 8 and weaken into a tropical depression as it passes over central Honshu overnight Sept. 8-9. The storm will continue to weaken as it enters the Sea of Japan and turns slightly to track northeastward off the coast of northwestern Honshu the morning of Sept. 9, dissipating over open waters late Sept. 9. Some uncertainty remains in the track and intensity forecast, and changes could occur in the coming days.

As of the morning of Sept 8, the Japan Meteorological Agency (JMA) has issued a bulletin regarding the storm system, warning of heavy rainfall, strong winds, and possible thunderstorms across eastern Japan and Tohoku Region through Sept. 9, as well as rough seas off the coasts of the Izu Islands and Kanto Koshin and Tokai regions. Rainfall totals of around 12 cm (5 inches) in Tokai Region, 15 cm (6 inches) in Tohoku Region, 25 cm (10 inches) in Kanto-Koshin Region, and 10 cm (4 inches) in the Izu Islands are forecast until at least the afternoon of Sept. 9. Wind gusts of up to 82 kph (51 mph) are possible in the Izu Islands and Kanto Region and up to 72 kph (45 mph) in Tokai Region Sept. 8. Waves up to 5 meters (16 feet) are likely in the waters of Kanto Region, Izu Islands, and Tokai Region Sept. 8. The JMA has also issued numerous yellow weather advisories (the lowest level on a four-tier scale) across central, southern and northern regions. Authorities will likely issue new warnings or update existing advisories throughout the system's progression in the coming days.

All Nippon Airways (ANA) have canceled flights to and from Hachijojima Airport (HAC) in southern Izu Islands and Shizuoka Airport (FSZ) Sept. 8. The airline also warned of flight disruptions at Fukushima Airport (FKS) in Fukushima Prefecture Sept. 8, and Tokyo's Haneda (HND) and Narita (NRT) international airports Sept. 8-9. Japan Airlines (JAL) states that its domestic flights to and from HND and NRT are experiencing irregular operations Sept. 8 due to the passage of the storm. JR Tokai has announced that there is a chance of suspensions on the Tokaido Shinkansen railway line Sept. 8.

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)