Delhi continued to grapple with severe air pollution on Sunday, with the city’s overall Air Quality Index (AQI) recorded at 439 at 7 am, firmly in the ‘severe’ category, according to the Central Pollution Control Board (CPCB). The situation had already worsened late Saturday night, when the AQI stood at 432 around 10 pm, before deteriorating further by Sunday morning.

Pollution levels remained alarmingly high across several parts of the national capital. Anand Vihar reported an AQI of 489, while Punjabi Bagh recorded 476 and Wazirpur 478. Other areas, including Ashok Vihar (463), Bawana (467), Chandni Chowk (464), Dwarka Sector 8 (469), RK Puram (467), ITO (448) and Narela (412) also remained in the ‘severe’ category, underlining the widespread nature of the pollution episode.

On the AQI scale, readings between 401 and 500 are classified as ‘severe’, posing serious health risks, particularly for children, the elderly, and people with respiratory or cardiovascular conditions.

The weather has further aggravated the situation. The India Meteorological Department (IMD) reported moderate fog at many places and dense fog at isolated locations across Delhi during the morning hours of Sunday, leading to reduced visibility. The city is likely to see a partly cloudy sky, with minimum temperatures between 4 and 6 degrees Celsius, remaining below normal, and maximum temperatures in the range of 21 to 23 degrees Celsius, which are above the seasonal average.

For Monday, the IMD forecasts shallow to moderate fog during the morning hours, with minimum temperatures rising slightly to 6–8°C, closer to normal levels. Maximum temperatures are expected to remain steady, with calm morning winds gradually picking up later in the day.

The IMD also warned that dense fog is likely to persist over parts of northwest India, including Delhi and adjoining regions, over the next few days, potentially affecting visibility and traffic during early morning and night hours.

Authorities have urged residents to limit outdoor activities amid severe pollution and winter fog, especially during the early morning, and to follow health advisories to reduce exposure to hazardous air quality.

Minimum temperatures on Sunday hovered between 5 and 7 degrees Celsius, remaining below normal by 1.6 to 3 degree Celsius.

In response to the deteriorating air quality, the Commission for Air Quality Management (CAQM) on Saturday reinvoked Stage-IV measures under the Graded Response Action Plan (GRAP) across Delhi and the National Capital Region (NCR).

"Keeping in view the prevailing trend of air quality and relevant factors and in an effort to prevent further deterioration of air quality in the region, the CAQM Sub-Committee on GRAP unanimously decides to invoke all actions as envisaged under Stage-IV of the extant GRAP - 'Severe ' Air Quality (DELHI AQI > 450), with immediate effect, in the entire NCR, as a proactive measure. This is in addition to the actions under Stages I, II & III of the extant GRAP already in force in NCR," the order from the CAQM read.