New Delhi, Jan 10 (IANS) Dense fog enveloped parts of the Delhi-National Capital Region (NCR) on Friday, reducing visibility to zero and affecting flight and train operations. The reduced visibility in Delhi-NCR delayed more than 150 flights for an average 41 minutes and about 26 trains.

Giving an update on the situation, the Delhi International Airport Limited (DIAL) said on Friday morning that flight departures had been “impacted” due to the dense fog. However, DIAL reassured worried passengers that CAT III-compliant flights can land and depart from the airport.

The India Meteorological Department (IMD) has issued a moderate to very dense fog warning for many parts of North India, including Punjab, Haryana and Rajasthan.

Hundreds of flights and trains have been cancelled or delayed due to thick fog in the past few weeks in North India.

Vehicles on Friday morning were seen crawling in parts of Delhi-NCR due to the poor visibility, with most drivers switching on their hazard lights to ensure they were visible to other drivers and prevent accidents.

The national Capital’s Air Quality Index (AQI) was recorded at 408 around 6 a.m., dropping to the ‘severe’ category from ‘very poor’, according to the data on the Central Pollution Control Board website.

In neighbouring Uttar Pradesh the AQI in Noida was recorded at 328 which is in the ‘Very Poor’ category, Greater Noida saw a ‘Poor’ AQI of 295 and Ghaziabad too was in the ‘Very Poor’ category as it touched 318.

In Haryana’s Gurugram and Faridabad the AQI was ‘Very Poor’ as it touched 303 and 317 respectively.

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’.

According to the IMD, Delhi’s minimum temperature was recorded at 9.6 degrees Celsius.

The weather agency said the capital’s maximum and minimum temperatures would hover between 6 and 20 degrees Celsius on Friday.

The Centre’s panel on Delhi-NCR’s air quality on Thursday re-implemented stage 3 curbs under the Graded Response Action Plan (GRAP) amid a sharp rise in air pollution levels owing to unfavourable meteorological conditions.