Delhi remained engulfed in dense fog on Monday. A red alert has been issued by the Indian Meteorological Department (IMD) and is set to remain in force until Tuesday afternoon, with authorities warning of extremely low visibility that could severely disrupt air, road, and rail movement across the capital and large parts of north India.
The IMD cautioned that travel conditions would remain hazardous through the day, urging commuters to exercise extreme caution.
Visibility drops to dangerous levels at IGI airport
Conditions turned critical at Indira Gandhi International (IGI) Airport, where visibility dropped to as low as 50 metres around 8 am, improving slightly to 100 metres an hour later, IMD data showed. The sharp decline in visibility triggered widespread disruption in flight operations.
According to officials and flight tracking platform Flightradar24, at least 128 flights were cancelled, eight were diverted, and nearly 200 flights faced delays, leaving thousands of passengers stranded or facing long wait times.
Delhi weather today and tomorrow
Delhi recorded a minimum temperature of 8.3 degrees Celsius, about 1.5 degrees above the seasonal average, while the maximum temperature settled at 22.5 degrees Celsius 2.1 degrees higher than normal, the IMD said. For Tuesday, the weather department has issued a yellow alert for dense fog during the morning hours, with temperatures expected to range between 8 and 21 degrees Celsius.
Delhi air quality slips into ‘severe’ category
The fog episode coincided with a sharp deterioration in air quality, pushing pollution levels into the danger zone. Delhi’s 24-hour Air Quality Index (AQI) surged past 405, placing it firmly in the ‘severe’ category, according to the Central Pollution Control Board (CPCB). On Monday, the AQI had stood at 390, classified as ‘very poor’.
Data from the CPCB’s SAMEER app showed ‘severe’ air quality at 24 monitoring stations, while 13 stations recorded ‘very poor’ levels. Wazirpur emerged as the most polluted area, registering an alarming AQI of 462. An AQI above 401 is considered ‘severe’, while readings between 301 and 400 fall under the ‘very poor’ bracket.
Airlines issues advisories as operations take a hit
With visibility remaining dangerously low, several airlines issued travel advisories warning passengers of possible delays and cancellations. IndiGo and SpiceJet cited “bad weather” and foggy conditions as key reasons for disrupted flight schedules. Air India warned that flight operations on Tuesday, December 30, could be affected across multiple cities due to poor visibility.
“Due to expected bad weather (poor visibility) in Delhi (DEL), Amritsar (ATQ), Jammu (IXJ), Ayodhya (AYJ), Gorakhpur (GOP), Varanasi (VNS), Darbhanga (DBR), Patna (PAT), Guwahati (GAU), and Bagdogra (IXB), all departures/arrivals and their consequential flights might get affected. Passengers are requested to keep a check on their flight status,” the airline said in a post on X.
IndiGo also issued multiple advisories, warning that fog was expected to intensify during late-night hours and continue into the morning, reducing visibility across several northern airports.
“In view of the forecast, flight movements may see some impact, with some delays possible as operations adjust to the prevailing conditions,” the airline said, adding that it was closely monitoring the weather situation.
The airline further cautioned passengers that poor visibility could affect road traffic during early morning hours and advised travellers to leave for the airport well in advance.
A few hours earlier, IndiGo said flight movements were slowing down as evening fog returned around Dehradun. “Our teams are continuing to support customers at the airport and are in close coordination with authorities to resume smoother operations as soon as conditions permit,” it said.
Earlier in the day, IndiGo cancelled around 80 flights across its network due to adverse weather conditions. Nearly half of these cancellations were from Delhi airport, while others involved routes connecting cities such as Mumbai, Bengaluru, Kochi, Hyderabad, Kolkata, Amritsar, Chandigarh, Jaipur, Dehradun, Indore, Patna, and Bhopal, according to airline data cited by PTI.
At around 11 am, IndiGo said foggy conditions continued to affect visibility across Delhi and several northern airports, warning that delays were likely to extend into the afternoon hours.
“We assure you that flight departures and arrivals are being sequenced to ensure steady and orderly movement, while keeping your journey and comfort in mind,” the airline said.