BEIJING, March 26-- Smog will persist to in north China, according to the National Meteorological Center (NMC).

The center issued a yellow alert for air pollution on Wednesday morning.

Beijing and Tianjin, as well as parts of Hebei and Shandong provinces expect "moderate" air pollution from Wednesday to Thursday morning, heavy in some place, according to the NMC forecast.

China's meteorological alerts are categorized as blue, yellow, orange and red as the severity ascends.

The weather center also expects light and moderate rains to sweep parts of southwest China and regions to the south of the Yangtze River from Wednesday to Friday.

Guangxi Zhuang Autonomous Region, and Hunan and Jiangxi provinces expect heavy rainfalls in the coming days. Some areas will experience torrential rains and thunderstorms.