The Asian nation is the world's biggest emitter of greenhouse gases that scientists say cause global warming and make extreme weather more frequent and intense.

Swathes of northern China have already been baked by heat waves this summer, while unseasonably torrential rains have triggered deadly floods and landslides across much of the south.

State broadcaster CCTV said Thursday the China Meteorological Administration's National Climate Centre forecasts that "air temperatures in most parts of the country will be somewhat higher... during the midsummer of this year".

"Against the climatic backdrop of global warming, average temperatures will rise and the occurrence of high-temperature weather will tend to be frequent," the centre said, according to CCTV.

The mercury will edge one to two degrees Celsius higher than normal in Zhejiang, Jiangxi, Hunan, Fujian, Guangdong and Gansu provinces as well as the regions of Guangxi and Ningxia, the report said.

However, it said northeastern provinces and the northern region of Inner Mongolia will see close to normal temperatures.

China ejects more planet-heating carbon dioxide into the atmosphere than any other country, but has pledged to bring emissions to a peak by 2030 and slash them to net zero by 2060.

Authorities tend to acknowledge the role of climate change in extreme weather but rarely link them directly to national emissions, and Chinese officials have brushed aside suggestions that Beijing could make more ambitious cuts.

The country saw an average of 2.6 high-temperature days -- those with maximum highs of 35 C (95 degrees Fahrenheit) or above -- in June, the fourth-highest figure since records began in 1961, CCTV cited the National Climate Centre as saying.

Heat records at 20 local weather stations broke historical records, the report added.

"As global warming intensifies, in recent years, high-temperature days in our country have... begun at earlier dates, occurred with increasing frequency, accumulated over longer periods, had a wider impact range and been generally stronger," it said.

Parts of northern China sweltered in temperatures of over 40 C last month.

And in eastern Anhui province this week, nearly a quarter of a million people were evacuated as rainstorms caused the mighty Yangtze and other rivers to swell.

Also in June, a landslide in Hunan killed eight people, and heavy rains and flooding left 38 dead in Guangdong.