Delhi shrouded in toxic smog, dense fog; IndiGo warns of flight delays

The IMD has forecast dense to very dense fog on Sunday and issued an orange alert for the national capital.

Delhi woke up on Sunday to a thick blanket of toxic smog and dense fog, sharply reducing visibility across the national capital and triggering stringent pollution curbs under GRAP Stage-IV. Several areas reported air quality in the ‘severe’ category, while flight operations continued to be affected by poor visibility.

Visuals from Ghazipur showed the area engulfed in heavy smog, with the Air Quality Index (AQI) touching 438, categorised as ‘severe’, according to the Central Pollution Control Board (CPCB). Around India Gate and Kartavya Path, a grey haze blanketed the city, with AQI recorded at 381, falling in the ‘very poor’ category.

Amid deteriorating conditions, the Commission for Air Quality Management (CAQM) invoked all measures under GRAP Stage-IV across Delhi-NCR to curb pollution levels.

IndiGo, late Saturday evening, issued a travel advisory, warning passengers that early-morning fog in Delhi and parts of northern India could disrupt flight operations. The airline said sudden drops in visibility during early hours may lead to delays, diversions, or schedule changes.

“Early-morning fog is expected to affect visibility across Delhi and northern India. Visibility may suddenly drop, impacting flight operations. Safety remains our top priority,” IndiGo said in a statement, adding that its operations teams were closely monitoring weather conditions to minimise inconvenience. Passengers were advised to check flight status before leaving for the airport and use the airline’s website to rebook or seek refunds if affected.

Delhi’s Indira Gandhi International Airport also issued a passenger advisory, confirming that low-visibility procedures were in place. Delhi International Airport Ltd (DIAL) said flight operations were functioning, but advised travellers to stay in touch with their respective airlines for real-time updates.

On Saturday, fog and poor visibility led to widespread disruptions, with at least 129 flights cancelled at Delhi airport, including 66 arrivals and 63 departures, officials said. Srinagar airport also reported four flight cancellations, including services to and from Delhi and Amritsar, due to adverse weather conditions.

The weather situation coincides with an intense cold spell across northern India. Delhi experienced its first cold wave of the season on Saturday, with the maximum temperature plunging to 16.9 degrees Celsius—5.3 degrees below the seasonal average—making it the coldest December day so far, according to the India Meteorological Department (IMD). The minimum temperature settled at 6.1 degrees Celsius, two degrees below normal.

Visibility remained poor for much of Saturday, dropping to as low as 200 metres at Safdarjung and 350 metres at Palam in the morning hours, before marginally improving by midday.

The IMD has forecast dense to very dense fog on Sunday and issued an orange alert for the national capital. Maximum and minimum temperatures are expected to hover around 23 degrees Celsius and 9 degrees Celsius, respectively.

Cold and foggy conditions also prevailed across Uttar Pradesh, Haryana and Punjab, where the IMD issued red alerts for dense to very dense fog and cold day conditions in several districts.