BEIJING, July 29 -- Rainstorms will hit China's northern and southwestern regions while the southeastern and northwestern areas will experience temperatures up to 39 degrees Celsius from midnight Saturday to Sunday, said the Chinese Central Meteorological Station.Meteorologists warned that strong rainstorms would cause floods in the provinces of Shaanxi, Shanxi, Hebei, Henan, Sichuan, Guizhou and Yunnan. Meanwhile, thunder and lightning would hit the rainy areas and southern Guangdong and Hainan provinces, threatening people's lives there.While high temperatures in the provinces of Zhejiang, Jiangxi, Fujian, Jiangsu, Hunan, Hubei and northern Guangdong would add to water and food supply pressures there and might bring drought, said the station.It also warned that landsides and mud-rock flows might happen in northeastern Sichuan and southern Shaanxi.Fierce rainstorms swept China this summer, triggering floods, landslides and mud-rock flows, which many experts believe to be a result of the global climate change.Chinese President Hu Jintao and Premier Wen Jiabao had urged local governments to improve weather monitoring, give priority to people's safety and properly relocate people in flood-hit areas amid the ongoing battle against floods.