Philippine Sea: Tropical Depression Yunyeung forms and tracking northeastward as of late Sept. 5

Event

Tropical Depression Yunyeung has formed in the central Philippine Sea and is tracking northeastward late Sept. 5. As of 21:00 JST, the system's center of circulation was approximately 1,548 km (962 miles) south-southwest of Yokosuka, Kanagawa Prefecture, Japan.

Forecast models indicate that the storm will strengthen into a tropical storm as it continues to track generally northeastward over the Philippine Sea Sept. 6-7. The system is expected to pass close to the southern Izu Islands, Tokyo Prefecture, Japan, early Sept. 8. The storm is then forecast to weaken as it continues to track northeastward off the coast of Honshu Island Sept. 8-9, remaining more than 150 km (93 miles) offshore. The system is then expected to weaken into a tropical depression as it turns to track east-northeastward away from Japan late Sept. 9-10. Uncertainty remains in the track and intensity forecast, and significant changes could occur in the coming days.

As of late Sept. 5 the Japan Meteorological Agency (JMA) has not issued any warnings directly related to the storm; however, warnings for severe weather are already in place across many parts of Japan. 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)