Typhoon Muifa gained strength on Wednesday ahead of its expected landfall on China's central coastal region of Zhenjiang on Wednesday evening.

The country was put on "red alert" and more than half of the scheduled flights from Shanghai's two main airports were canceled.

Muifa is expected to hit land close to the city of Ningbo, just to the south of Shanghai. Ningbo and other nearby cities also canceled flights and ordered tankers to remain anchored during the storm.

Maximum sustained winds reached 145 kilometers (90 miles) per hour, the Hong Kong observatory said.

Authorities in Shanghai warned that strong winds and torrential rains were expected until Thursday. China's busiest container seaport was also expecting waves of up to 5 meters (16 feet).

Unusually hot summer behind strong typhoon

Authorities in Zhenjiang also issued a "red warning" for flash floods as the national weather forecaster warned that small and medium rivers could burst their banks.

The collective populations of the three cities facing the brunt of the storm — Shanghai, Ningbo, Zhoushan and Taizhou — have a total population of 42.46 million people.

According to meteorologists, this summer's unusually high temperatures have caused what the Chinese financial magazine Caixin reported would be the strongest Typhoon in the Yangtze River Delta in a decade.

Parts of China have been experiencing drought conditions due to a lack of rain and the sweltering heat.

The Central Meteorological Administration (CMA) said on Tuesday that Muifa — China's 12th typhoon of the year — would move northwest after making landfall and then begin to dissipate.

ab/aw (Reuters, AP)