Cities across China have been warned of extreme heat. Tens of millions of people have been advised to stay at home, and record temperatures have led to an overload of energy supplies, AFP reported.

In recent months, extreme and deadly heatwaves have hit from Western Europe in July to India from March to April. Scientists say extreme weather events have become more frequent due to climate change and are likely to intensify as global temperatures continue to rise.

China is no exception and is experiencing one of the hottest years on record.

In the eastern provinces of Zhejiang and Fujian, temperatures rose above 41 degrees Celsius, reaching record levels in two cities.

People in areas at risk of red heat, mostly concentrated in the southeast and northwest, have been ordered to cease all outdoor activities and pay special attention to fire prevention, multiple National Weather Service notices over the weekend said.

Earlier this month, Shanghai recorded its hottest temperature of 40.9°C since records began in 1873.

China's power grid is also under pressure due to increased demand for air conditioning, with the country's largest power plants producing record volumes in mid-July.

Some local governments this month resorted to turning off street lights and raising electricity rates for factories during peak periods.

The ongoing heat wave, which has hit the lower Yangtze River particularly hard, will also negatively affect local crops, said Fu Jiaolan, chief forecaster at the National Meteorological Center.