Delhi's air quality is set to worsen significantly in the coming days, with predictions indicating that the Air Quality Index (AQI) could reach the 'severe' category (AQI above 400) on Tuesday, following Diwali celebrations. Currently, the AQI is already in the 'poor' range, having recorded levels of 268 on Saturday. Experts attribute the expected spike in pollution to emissions from firecrackers, vehicular emissions, and dust, compounded by weather conditions that trap pollutants close to the ground.

The Air Quality Early Warning System (EWS) has forecasted that the AQI will deteriorate to 'very poor' on Monday and could breach the 'severe' mark on Tuesday. Areas like Ashok Vihar and Wazirpur have already reported hazardous levels, with AQI readings between 326 and 412. Health experts warn that breathing the air in Delhi is equivalent to smoking about six cigarettes a day, based on PM2.5 exposure.

Gufran Beig, founder of SAFAR, noted that while stubble burning from Punjab may have a lesser impact this year due to delayed harvesting, excessive use of firecrackers could still lead to a significant rise in pollution levels. He mentioned, "The silver lining is that La Niña-induced strong winds are expected on Tuesday, which may help disperse pollutants and bring the AQI down to the 'very poor' range later in the day."

Activists and health professionals are raising alarms about the potential health risks associated with the deteriorating air quality. Bhavreen Kandhari, an activist, stated, "Firecrackers — even so-called ‘green' ones — release sulphur, heavy metals and fine particulates like PM2.5. In stagnant winter air, even limited use compounds the problem, triggering a haze and a public health emergency that can last for days."

The Central Pollution Control Board (CPCB) categorizes AQI levels as follows: 0-50 is 'good', 51-100 is 'satisfactory', 101-200 is 'moderate', 201-300 is 'poor', 301-400 is 'very poor', and over 400 is 'severe'. With the festival week approaching, experts advise residents to wear masks and limit outdoor activities to mitigate health risks associated with the rising pollution levels. The India Meteorological Department has also forecasted shallow fog and smog in the mornings, with temperatures ranging from 18-34 degrees Celsius in the coming days.