Dense to very dense fog conditions are very likely in Punjab, Haryana, Chandigarh, Delhi and Uttar Pradesh during December 28 night to December 30, said IMD. Dense fog conditions are also likely in Rajasthan, Madhya Pradesh on December 29-30, Odisha during December 29-31, Bihar on December 30-31, Assam, Meghalaya, Nagaland, Manipur, Mizoram and Tripura from December 29 to January 1.