Delhi recorded the season’s lowest temperature of 5.2°C on Tuesday as a cold wave engulfed northern India, IANS reported. The India Meteorological Department said the temperature was likely to drop further to 4°C on Wednesday.

“The sky will remain clear with mist and shallow fog in some isolated places in the morning,” an IMD official told the news agency. The department said temperatures would not go above 17°C till the cold wave recedes on January 13.

Railway officials said that at least 21 trains were running late because of dense fog, and that seven trains had to be cancelled, while they rescheduled nine others. The cancelled trains include the New Delhi-Hyderabad Telangana Express, Jammu Tawi- Bhagalpur Amarnath Express, Jaynagar-Amritsar Saryu Yamuna Express, New Delhi-Rajgir Shramjivi Express, Kota-Patna Express, New Delhi-Bhubaneswar Rajdhani Express and Amritsar-Kanpur Central Express.

Officials, however, said operations at the city’s Indira Gandhi International Airport were still unaffected. On Monday, the Centre had issued a cold wave warning for regions in north India, saying that the minimum temperature is likely to fall by 2-4°C between January 10 and January 13.