The sky remained shrouded in dull grey, while a thick haze descended upon the capital on Saturday, with the air quality on the brink of "severe". At 4 pm, Delhi's 24-hour average Air Quality Index (AQI) was recorded at 398 -- just two points shy of the threshold -- while several monitoring stations across the city reported readings in the 'severe' category. Meanwhile, hourly AQI readings from the CPCB's SAMEER app showed that air quality worsened during the evening hours, slipping into the severe category at 401, at 5 pm. Of the 40 monitoring stations across the city, 22 recorded air quality in the severe range, while 17 logged readings in the 'very poor' category. Chandni Chowk reported the worst air quality, with an AQI reading of 464, in the 'severe plus' category. With the sun largely obscured by clouds and suspended pollutants, visibility was greatly reduced. Amid prevailing cold-wave conditions, the average air quality in the capital deteriorated to 398 on Saturday, compare