According to IMD, visibility recorded at 5:30 am today was 200 meters and less in several parts.
Several states in the northern part of the country are reeling under a severe cold wave.
According to the India Meteorological Department (IMD), cold day to severe cold day conditions are very likely in many pockets over Punjab, Haryana, Chandigarh, Delhi and Uttar Pradesh.
Bone-chilling cold winds have affected isolated places in Bihar, Uttarakhand, Rajasthan and Sub-Himalayan West Bengal, and Sikkim.
"Dense to very dense fog is very likely in many pockets over East Uttar Pradesh; in some pockets over Punjab, Haryana, Chandigarh and Delhi," the IMD stated in its All India Weather Warning Bulletin.
According to the weather forecast agency, fog is also likely in isolated pockets of West Bengal, Sikkim, Assam, Meghalaya and Mizoram, and Tripura in the morning hours.
Thunderstorm accompanied with hail and lightning is very likely at isolated places over East Madhya Pradesh and Chhattisgarh and also in few parts of Jharkhand and Coastal and south interior Karnataka.
Most of the northern parts of India have been engulfed by fog. According to IMD, visibility recorded at 5:30 am today was 200 meters and less in several parts.
For instance, in Churu, Lucknow, Baharaich and Dibrugarh the visibility was 25 meters each while in Patiala, Chandigarh, Dehradun, Gwalior and Guwahati it was only 50 meters each.
In Ambala, Bareilly, Bikaner, Sultanpur and Purnea the visibility was only 200 meters each.