Bone-chilling cold conditions prevailed in north India on Friday with fresh snowfall in Jammu and Kashmir and Himachal Pradesh, as a foggy morning in Delhi delayed 760 flights and led to cancellation of 19, while over 100 trains remained up to two hours behind schedule. The national capital also braved a cold day with minimum temperature settling at 6.4 degrees Celsius. Officials said visibility reduced to zero at some places in the morning affecting and train and plane services.