Dense fog enveloped the Uttar Pradesh state capital on Thursday morning along with icy winds bringing down the mercury.

Regional Met Office Director J.P. Gupta said the fog would continue and visibility would remain poor.

Heavy snowfall in the hilly regions of Jammu and Kashmir, Himachal Pradesh and neighbouring Uttarakhand is likely to add to the bite, he added.

"The snowfall in the hilly regions has been the maximum in almost a decade and its affect is set to add to the winter chill in states like Delhi and UP," Gupta noted.

In the past 24-hours, Agra with 7 degrees Celsius was the coldest in the state, followed by Gorakhpur (8), Lucknow (8), Allahabad (8.5), Kanpur (9.2) and Varanasi (10).