Intense cold wave conditions will continue in Uttar Pradesh and will last for over four days, the Met office announced on Monday.

The mercury has been hovering between 1.4-2.2 degrees Celsius in the past three days in most parts of UP but climbed to 4 degrees Celsius on Sunday.

After remaining sunny all day, fog returned in the state capital late Sunday disrupting traffic.

"Snowfall is continuing intermittently in the hill states and another round of moderate to very heavy snowfall in neighbouring Uttarakhand, Himachal Pradesh and Jammu and Kashmir is expected within the next few days," the weather office said.

Many trains were running behind schedule due to poor visibility and fog in the Northern (NR) and North-Eastern Railways.

An official told IANS that Patna-Kota Express was late by 19 hours and Himgiri Express by 13 hours on Sunday. Jammu Tawai-Gorakhpur Express was cancelled.

The Neelanchal Express, Kumbh Express, Vaishali Express, Pratapgarh-Bhopal Express, Raptiganga Express, Marudhar and Kashi-Vishwanath Express running between Varanasi and New Delhi are also behind schedule.