Dense fog enveloped parts of Delhi and the National Capital Region (NCR) this morning, significantly reducing visibility and resulting in disruptions to travel. More than 150 flights were delayed, with an average delay of 41 minutes, as reported by aviation website FlightRadar24. Additionally, around 26 trains were delayed or cancelled due to the thick fog. The Delhi International Airport Limited (DIAL) confirmed that departures were impacted but assured travelers that CAT III-compliant flights could still land and depart.

The India Meteorological Department (IMD) issued a warning of moderate to very dense fog for many parts of North India, including Punjab, Haryana, and Rajasthan. This has added to the string of cancellations and delays that have plagued North India over the past few weeks due to similar foggy conditions.

Alongside the fog, Delhi's air quality index (AQI) was recorded at 408 at around 6 a.m., entering the ‘severe’ category, which is an alarming level of pollution. An AQI of 408 is considered extremely hazardous, impacting health, especially for those with respiratory issues. In response to the rising air pollution levels, the Centre's panel on air quality in Delhi-NCR re-implemented Stage 3 curbs under the Graded Response Action Plan (GRAP) on Thursday.

Stage 3 curbs under GRAP include a ban on non-essential construction work, the requirement for schools up to grade V to switch to hybrid learning or online education, and restrictions on BS-III petrol and BS-IV diesel vehicles in Delhi and the surrounding NCR districts. Additionally, diesel-operated medium goods vehicles with outdated BS-IV emissions standards are also banned.

The IMD has forecasted that Delhi’s temperatures will range between 6 and 20 degrees Celsius, with the minimum temperature recorded at 9.6 degrees Celsius. The thick fog, combined with the worsening air pollution, has caused serious disruptions to daily life and travel in Delhi-NCR, and residents are advised to take precautions against the deteriorating air quality.