Mumbai and Thane recorded severe air quality readings on Diwali night, with AQI at 278 and 298, respectively, as firecracker emissions added to the city's pollution burden. New Delhi, Nov 8 (PTI) Delhi's air quality was in the 'very poor' category on Sunday, but set to worsen after Diwali celebrations in the. Delhi AQI hits 371 at 7pm, netizens report smelling smoke as Diwali celebrations gather pace | Latest News.