East China Sea: Typhoon Muifa tracks north-northwestward late Sept. 13; landfall forecast in northeastern Zhejiang Province, China, late Sept. 14 /update 6

Event

Typhoon Muifa was tracking north-northwestward over the East China Sea late Sept. 13. As of 20:00 CST, the system's center of circulation was approximately 305 km (189 miles) northeast of Taipei, Taiwan.

Forecast models indicate that the storm will slightly weaken before making landfall over northeastern Zhejiang Province, China, late Sept. 14 and Shanghai and southern Jiangsu Province late Sept. 14-early Sept. 15. The system is then forecast to weaken further into a tropical storm as it tracks north-northwestward across Jiangsu Province Sept. 15 before transitioning into a post-tropical cyclone over Shandong Province by late Sept. 16 and then dissipating. Some uncertainty remains in the track and intensity forecast, and significant changes could occur in the coming days.

As of late Sept. 13, the China Meteorological Administration had issued an orange typhoon warning (the second-highest level on a four-tier scale), cautioning that strong winds are forecast over many eastern coastal waters, as well as Shanghai and coastal areas of Zhejiang and Jiangsu through at least 20:00 Sept. 14. Additionally, heavy rainfall is likely in parts of Shanghai, Zhejiang, Jiangsu, and eastern Shandong over the same period; notably, rainfall totals of 25-28 cm (9-11 inches) are forecast in northeastern Zhejiang Province.

As of early Sept. 14, the Taiwan Central Weather Bureau had issued yellow heavy rain advisories (lowest level on a four-tier scale) for Yilan County and Keelung, Taipei, and New Taipei cities, likely in connection with the storm.

The Japan Meteorological Agency (JMA) has rescinded all orange-level (the middle level on a three-tier scale) weather warnings previously issued in connection with the storm. Yellow advisories for high waves, likely associated with the tropical cyclone, notably remained in place across Okinawa Prefecture as of early Sept. 14.

Officials will likely issue relevant weather alerts and warnings over the coming days as the system progresses.

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 other regional airports and temporary closures of ports may occur. 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 typhoon or 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 storm's path, 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
China Meteorological Administration
Taiwan Central Weather Bureau
Japan Meteorological Agency