It was a cold foggy Thursday morning in the national capital with the minimum temperature settling at 4.2 degrees Celsius, three notches below the average in the season. Railways officials said 11 north-bound trains, including the Purushottam Express, Bhubneshwar-Delhi Duranto, Poorva Express, Brahmputra Mail, were running late by an average of 2-3 hours. The fog dropped visibility in various parts of the city. The visibility was 400 metres at Safdarjung at 8.30 am and 250 metres at Palam at 7.30 am, said a MeT department official. Relative humidity was 100 per cent in the morning. As per forecast of the department, the day will be marked with clear skies. Haze and smoke will occur later in the day, the weatherman said. The maximum temperature would be around 22 degrees Celsius. On Wednesday, the maximum and minimum temperatures were 21.3 degrees Celsius and 4.5 degrees Celsius, respectively.