Dense fog across Northern India, particularly Delhi, has caused widespread disruptions to air travel on December 30, 2025. Over 118 flights were cancelled and more than 200 delayed at Delhi's Indira Gandhi International Airport, with 16 flights diverted. Airlines issued advisories, and the Airport Authority of India warned of potential delays. Visibility dropped significantly, impacting operations for flights not compliant with CAT III standards. Air quality in Delhi remained in the 'very poor' to 'severe' category.