BEIJING, Oct. 29  -- Heavy rains will hit south China and areas along the middle and lower reaches of the Yangtze River, while haze is expected to shroud north China over the next three days, the National Meteorological Center (NMC) said on Wednesday.

The center continued to issue a blue alert for rainstorms on Wednesday, saying that heavy rains will sweep parts of Chongqing Municipality and Guizhou, Hunan, Hubei, Jiangxi, Anhui and Jiangsu provinces.

Some areas will see precipitation of up to 100 to 120 mm, said the center.

The country's weather observatory also forecast that smog will hit areas along the Yellow and Huaihe rivers, as well as north China in the coming days. Parts of Hebei Province will see heavy haze on Thursday.

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