Beijing experienced serious smog on Saturday despite showers over past two nights, the Beijing Environmental Protection Monitoring Center said.

The Air Quality Index (AQI) reading was 229 at 6 p.m. Saturday, meaning serious pollution, with the major pollutant being PM2.5, particulate matter measuring less than 2.5 microns in diameter, said the center.

Wang Buying, engineer with the center, forecast the smog would persist until Monday night when a cold snap will arrive.

The density of PM2.5 in Beijing decreased by 12.5 percent year on year in January to August, according to the Beijing Environmental Protection Bureau.

The average PM2.5 reading in the first eight months was 63 micrograms per cubic meter.

Beijing is aiming to keep average PM2.5 levels below 60 micrograms per cubic meter in 2017. In 2015, the level was 80.6 micrograms, down from 95.7 micrograms in 2012.