When the fireworks light up the night to celebrate Lunar New Year in Beijing, air quality in the capital will get worse, possibly leading to three days of severe pollution, the municipal environmental watchdog said on Monday.

The weather from Wednesday to Friday is expected to be windless, which means air pollutants near the ground will not be dispersed, said Li Yunting, director in charge of air quality at the Beijing Environmental Monitoring Center.

Those windless days correspond to the heaviest use of firecrackers. Lunar New Year, or Spring Festival, falls on Thursday.