East China Sea: Tropical Storm Khanun approaching Goto Islands, Nagasaki Prefecture, Japan, as of late Aug. 9 /update 16

Event

Tropical Storm Khanun is tracking northward in the East China Sea and is expected to pass over the western end of Fukue Island in the Goto Islands, Nagasaki Prefecture, Japan, late Aug. 9. As of 21:00 JST, the system's center of circulation was approximately 115 km (71 miles) southwest of Sasebo, Nagasaki Prefecture, Japan.

Forecast models indicate that having passed the Goto islands, the storm will weaken slightly as it enters the Korea Strait late Aug. 9-early Aug. 10 and tracks north-northwestward towards southern South Korea. The system is forecast to make landfall over southeastern South Gyeongsang Province early Aug. 10. The storm is forecast to weaken as it tracks north-northwestward across South Gyeongsang Province, northeastern North Jeolla Province, eastern South Chungcheong Province, Daejeon City, Sejon City, and Gyeonggi Province through Aug. 10, before entering North Korea early Aug. 11. The system is expected to weaken into a tropical depression as it continues to track north-northwestward over North Korea's eastern South Hwaghae, western North Hwanghae, western South Pyongan, and western North Pyongan provinces through Aug. 11. The remnants of Khanun will likely dissipate over Liaoning Province in northeastern China Aug. 12. Uncertainty remains in the track and intensity forecast, and significant changes could occur in the coming days.

As of late Aug. 9, the Japan Meteorological Agency (JMA) has issued purple (the highest level on a three-tier scale) heavy rain and landslide warnings across much of Southern Kyushu Region and parts of Kumamoto Prefecture in Northern Kyushu Region. Red heavy rain, landslide, flood, storm/gale, and high wave warnings have been issued across much of northern and southern Kyushu and parts of Shikoku regions. Yellow warnings for various weather phenomena are in effect across much of the rest of western and central Japan. The JMA has advised residents to move into a sturdy building and stay away from windows indoors, be extremely vigilant against strong winds, and be careful of high waves. The heaviest rainfall totals of around 30 cm (12 inches) are likely in southern Kyushu and Shikoku through Aug. 10-11, as well as 25 cm (10 inches) in northern Kyushu. Winds gusting up to 144 kph (89 kph) are likely in parts of western Japan, as well as rough seas generating waves up to 7 meters (23 feet).

The Korea Meteorological Administration has issued typhoon warnings (the highest level on a two-tier scale) across much of Jeju, South Gyeongsang, and South Joella provinces, as well as Busan and Usan cities, in southern South Korea as of late Aug. 9. Typhoon advisories have been issued across the rest of the southern half of the country, and heavy rain warnings are in place across eastern and northeastern regions. The China Meteorological Administration has issued a blue typhoon warning (the lowest level on a four-tier scale), warning of rough seas in eastern coastal waters and heavy rainfall over parts of Jilin Province Aug. 9-10.

Authorities have confirmed two fatalities as the system passed through Okinawa Prefecture late Aug. 1. At least 88 other people were also injured in Okinawa Prefecture. At least nine people have been injured in Fukuoka, Kagoshima, and Kumamoto prefectures as of late Aug. 9, and minor damage and landslides have been reported in Kagoshima and Miyazaki prefectures. Authorities are maintaining evacuation orders for hundreds of thousands of people across parts of Kagoshima, Kumamoto, Miyazaki, Nagasaki, and Saga prefectures, including a black ensure safety evacuation warning (the highest level on a three-tier scale) for Kobayashi City in Miyazaki Prefecture; full details on areas under evacuation can be found here. As of late Aug 9, more than 10,000 households in Kagoshima Prefecture, nearly 1,000 in Miyazaki Prefecture, and more than 2,000 in Nagasaki Prefecture are without power.

Airlines canceled hundreds of flights across the Ryukyu Islands and Kyushu Aug. 1-9. Oita Airport (OIT) canceled all flights from Aug. 9 and has closed the terminal building through at least early Aug. 10. Further flight cancellations and delays are likely due to the adverse weather conditions. Many rail and ferry services across Kyushu have been suspended until further notice due to the passing of the storm.

More than 200 flights and ferry services to Jeju Island were canceled in South Korea Aug. 9; further cancelations are likely in the coming days as Khanun approaches the south coast. Around 36,000 people attending the World Scout Jamboree in Saemangeum were evacuated to less exposed locations in towns and cities across South Korea Aug. 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. Additional 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)
China Meteorological Administration
Korea Meteorological Administration