Yellow Sea: Tropical Depression Pulasan tracking eastward across Yellow Sea as of early Sept. 21 /update 7

Tropical Depression Pulasan is tracking eastward across the Yellow Sea, early Sept. 21, having made landfall over the northeastern island areas of Zhejiang Province and Shanghai in China Sept. 19. As of 06:00 KST, the system's center of circulation was approximately 587 km (365 miles) west-southwest of Chinhae, South Gyeongsang Province, South Korea.

Forecast models indicate that the weather system will strengthen back into a tropical storm as it turns to track east-northeastward before making another landfall over South Joella Province in South Korea the afternoon of Sept. 21. The system will likely strengthen slightly as it tracks east-northeastward across southern South Korea and enters the Sea of Japan Sept. 21 before making landfall over the Oki Islands, Shimane Prefecture, Japan, early Sept. 22. Pulasan is forecast to transition into a remnant low as it tracks east-northeastward in the Sea of Japan and makes another landfall in Ishikawa then Niigata prefectures, Japan, the afternoon of Sept. 22. Some uncertainty remains in the track and intensity forecast, and changes could occur in the coming days.

The China Meteorological Administration is maintaining a blue typhoon warning (the lowest level on a four-tier scale); strong winds are forecast across parts of the Yellow Sea and southeastern China.

As the storm approaches, the Korea Meteorological Administration has warned of strong winds and heavy rainfall in southern regions, including Jeju Island. As of early Sept. 21, authorities have issued rainfall warnings for parts of Jeju, southern North Chungcheong, western North Gyeongsang, northern North Jeolla, southern South Chungcheong, and southern South Gyeongsang provinces, as well as Busan and Ulsan metropolitan cities. Rainfall advisories are in place across most of the rest of South Korea. Gale warnings and strong wind advisories are in place for southern and central South Korea.

Authorities in Shanghai have evacuated around 112,000 people due to the storm as of early Sept. 21. Operators have suspended dozens of rail and ferry services in the region.

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, rendering 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.