August was marked by extremely hot temperatures in parts of China, prompting temporary power rationing in some regions.
Asia-Pacific markets fell ahead of China's inflation and trade data for September.
China is slated to release inflation numbers early Friday.
Analysts polled by Reuters expect the country's consumer price index to climb 0.2% year-on-year, compared to 0.1% in the previous reading.
Hong Kong's Hang Seng index looks set to drop, with futures at 17,911 compared to the HSI's close of 18,238.21.
Organizations:
heatwave, Reuters, Nikkei
Locations:
China, Chongqing's, Asia, Pacific, Japan