Japan: Typhoon Shanshan tracking northwestward across Philippine Sea as of early Aug. 27 /update 3

Typhoon Shanshan is tracking northwestward across the Philippine Sea early Aug. 27. As of 12:00 JST, the system's center of circulation was approximately 554 km (344 miles) south of Sasebo.

Forecast models indicate that the weather system will strengthen further as it passes just northeast of the Amami Islands, Kagoshima Prefecture, late Aug. 27, before weakening slightly as it turns to track northwards and makes landfall over Suwanosejima in the Tokara Islands the afternoon of Aug. 28. Shanshan is forecast to weaken slightly and make another landfall over far northwestern Kagoshima Prefecture early Aug. 29. After landfall, the system is likely to weaken into a tropical storm as its tracks northeastward across Kyushu and exit into the Seto Inland Sea early Aug. 30 before making another landfall over Ehime Prefecture the afternoon of Aug. 30, continuing northeastward and making a subsequent landfall over Okayama Prefecture early Aug. 31. Shanshan is forecast to weaken further but remain at tropical storm strength as it tracks northeastward across the Kansai then Chubu regions through early Sept. 1. Some uncertainty remains in the track and intensity forecast, and changes could occur in the coming days.

As of early Aug. 27, the Japan Meteorological Agency (JMA) has issued a bulletin warning that the typhoon will track westward and approach the Amami region Aug. 28 before turning to track north and approach western Japan Aug. 29, bringing strong winds, high waves, landslides, and flooding. Heavy rainfall of 30 cm (12 inches) in the Amami region, 20 cm (8 inches) in the Tokai and southern Kyushu regions, and 10 cm (4 inches) across the rest of western Japan are forecast through early Aug. 28. After which, heavier rainfall of 50 cm (20 inches) in southern Kyushu, 40 cm (16 inches) in the Amami region, 30 cm (12 inches) in the Shikoku region, and 20 cm (8 inches) in the Kinki, northern Kyushu, and Tokai regions are forecast through early Aug. 29. Swells and heavy seas are likely across western Japan; the highest waves of up to 10 meters (33 feet) are forecast over the Amami region Aug. 27 and in southern Kyushu Aug. 28.

The JMA has issued purple (highest level on a three-tier scale) storm surge warnings across the Amami Region and red high wave warnings across the Tanegashima and Yakushima regions in Kagoshima Prefecture. Authorities will likely issue new warnings or update existing advisories throughout the system's progression in the coming days.

Authorities have issued purple evacuation orders (the second highest level on a five-tier scale) for Amami City in Kagoshima Prefecture and parts of Hamamatsu and Kosai cities in Shizuoka Prefecture. Red evacuation orders for the elderly and other vulnerable people remain in effect for some locations in Kagoshima, Shiga, and Shizuoka prefectures.

Japan Airlines (JL) has canceled more than 100 domestic flights Aug. 27-28, mainly at Kagoshima Airport (KOJ) and Amami Airport (ASJ) and six international flights connecting Kansai Airport (KIX) and Chubu Centrair International Airport (NGO) with Shanghai Pudong International Airport (PVG) in China and Suvarnabhumi Airport (BKK) in Bangkok, Thailand Aug. 28. Various other airlines have warned that flight cancellation and delays are possible across western Japan over the coming days. Authorities have warned that cancellations or delays are possible on parts of the Kyushu Shinkansen from Aug. 27, on the Sanyo Shinkansen Aug. 29-30, and on the Tokaido Shinkansen Aug. 29-31.

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.

Inclement weather could trigger localized business, transport, and utility disruptions and render some bridges or roadways impassable. Flight disruptions at regional airports and temporary port closures 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.