Toxic smog blanketed Delhi on Monday as air quality plunged deeper into the ‘Severe’ category, with the Air Quality Index breaching 460 and visibility dropping sharply across the capital.
The worsening pollution disrupted flight and train schedules, underlining how dangerous the winter air crisis has become for residents.
Although air quality has been deteriorating steadily since the end of the monsoon, the past three days have pushed Delhi and its surrounding National Capital Region into what experts describe as a public health emergency.
Falling temperatures, stagnant wind patterns, and sustained emissions from vehicles and industries have combined to trap pollutants close to the ground, creating a lethal mix that lingers through the day.
Data from the Central Pollution Control Board shows that Delhi’s AQI remained in the ‘Very Poor’ range, between 259 and 372, during the first half of December 2025, before conditions worsened dramatically after December 12. The AQI jumped to 431 on December 13, climbed further to 461 on December 14, and stood at 427 on December 15, firmly placing the capital in the ‘Severe’ zone where prolonged exposure can have serious health consequences. By 4:00 pm on December 15, 29 of Delhi’s 39 monitoring stations were recording AQI levels above 400.
Wazirpur emerged as the worst-affected area with an AQI of 486, followed closely by Jahangirpuri at 481, Anand Vihar at 480, Ashok Vihar at 478, and Vivek Vihar at 475. Even NSIT Dwarka, the city’s least polluted station at the time, recorded an AQI of 356, which still fell in the ‘Very Poor’ category.
The crisis has spread well beyond the capital, with NCR cities also gasping under hazardous air.
Greater Noida reported an AQI of 447, Ghaziabad 444, and Noida 437, all classified as ‘Severe’, while Bahadurgarh at 374 and Meerut at 360 remained ‘Very Poor’. Gurugram and Manesar hovered between 325 and 345, offering little respite from the choking conditions. In stark contrast, CPCB data highlights a sharp regional divide across the country.
While North India struggles under toxic smog, much of southern and eastern India continues to record comparatively cleaner air, with cities like Chennai, Bengaluru, and Hyderabad staying in the ‘Moderate’ category and hill stations such as Gangtok and Shillong enjoying ‘Good’ air quality.
Health experts warn that sustained exposure to such extreme pollution levels can trigger respiratory and cardiovascular illnesses and worsen long-term health outcomes, particularly for children, the elderly, and those with pre-existing conditions.
In response to the crisis, authorities have banned construction activities, advised residents to limit outdoor exposure, and shifted schools across Delhi-NCR to online classes.
However, experts caution that these temporary measures are not enough and are calling for urgent, sustained action, including stricter emission norms, aggressive control of vehicular pollution, and long-term urban planning reforms, to prevent Delhi’s winters from turning toxic year after year.