Delhi’s air quality worsened on Diwali, with 34 of 38 monitoring stations in the ‘Red Zone,’ showing ‘very poor’ to ‘severe’ levels. The city’s 24-hour AQI rose to 345 from 326, with Dwarka and Wazirpur above 400. Transport and industrial emissions contributed heavily. Authorities invoked Stage II of the GRAP, expecting conditions to worsen in the coming days.