BEIJING, May 18 (Xinhua) -- China's national weather observatory renewed a blue alert for rainstorms on Friday, as western, central, southern and eastern areas will continue to be hit by heavy rain till Saturday.

Heavy rain or storms may hit parts of Anhui, Chongqing, Henan, Hubei, Hunan, Jiangxi and Sichuan, while some of these areas may see thunderstorms and gales, according to the National Meteorological Center (NMC).

Rainfall could exceed 100 millimeters per hour in some regions of Henan and Hubei, the NMC said.

The NMC warned local authorities to reduce outdoor activities and take precautions against flooding, disastrous mountain torrents and landslides.

China has a four-tier color-coded weather warning system, with red the most severe, followed by orange, yellow and blue.