Amid the prevailing cold wave conditions in the national capital region where the mercury is standing at seven degrees Celsius, Delhi on Wednesday morning woke up to a thick blanket of fog that covered parts of Delhi-NCR and caused visibility to drop to almost zero. Besides Delhi-NCR, the entire North India has been grappling with a cold wave as temperatures continue to plummet in Uttar Pradesh, Bihar, Rajasthan, Uttarakhand, and Delhi-NCR.