A thick blanket of fog rolled over Delhi-NCR and other adjoining areas on Thursday evening as mercury dipped further in the national capital. As per the India Meteorological Department (IMD), 'dense to very dense' fog is likely to engulf Delhi on Thursday night and Friday early morning.

Very dense fog is expected in the national capital in the next five days, while the minimum temperature is expected to hover around seven to eight degrees Celsius, the weather department said on Thursday.

Delhi recorded a minimum temperature of 8.4 degrees Celsius, one notch above the season's average, while the maximum temperature settled at 21.4 degrees Celsius, one notch above normal, according to the India Meteorological Department (IMD).

The IMD has also issued a dense fog warning for Delhi, Haryana and Chandigarh during the late and early hours until December 31.

In an advisory for dense fog, the department has asked drivers to use fog lights and travellers to stay updated on the schedules of airlines, railways and state transport. "Exercise caution while driving or using any mode of transportation," the IMD said.

Reduced visibility also hit the railway services, with 22 Delhi-bound trains delayed on Thursday. The relative humidity at 5.30 pm was 82 per cent in Delhi, the IMD said.

The Central Pollution Control Board (CPCB) data stated that Delhi's 24-hour average AQI on Thursday settled at 358. An AQI between zero and 50 is considered "good", 51 and 100 "satisfactory", 101 and 200 "moderate", 201 and 300 "poor", 301 and 400 "very poor", and 401 and 500 “severe.”

Dense fog delays flights

Flight operations continued to be impacted by dense fog at the Delhi airport for the third day on Thursday, with nearly 60 flights getting diverted and scores getting delayed during this period.

Airport sources said a total of 58 flights, the majority of them operated by domestic carriers, were diverted due to bad weather between 0000 hours of December 25 to 0600 hours of December 28.

Most of the flights had to be diverted, as the pilots were not trained to operate flights in low visibility conditions, the sources claimed.

On Wednesday, Delhi Airport issued a fog alert on social media platform X. "While landing and takeoffs continue at Delhi Airport, flights that are not CAT III compliant may get affected.

"Passengers are requested to contact the airline concerned for updated flight information. Any inconvenience caused is deeply regretted," it had said.

Noida schools to remain shut

As per the order issued by Basic Education Officer Rahul Panwar, the Gautam Buddh Nagar administration on Thursday ordered the closure of all schools across Noida and Greater Noida on Friday and Saturday due to cold weather conditions. However, teachers and other staffers would continue to work on Friday and Saturday.

"In compliance with the instructions given by District Magistrate, Gautam Buddh Nagar, Maneesh Kumar Verma in view of the dense fog and extreme cold, all the boards (CBSE/ICSE/IB and others) recognised schools, council schools, government schools or non-government aided schools will observe holiday on December 29 and 30," Panwar said.

The order applies to all classes from nursery to 12, he said in the order. "All the teachers and employees working in the said schools will continue to be on duty as usual," the officer added. 

(with PTI inputs)