A cold wave is intensifying across North India, including Delhi-NCR, as temperatures dip following light rain in the plains and snowfall in the mountains. Delhi is grappling with a double threat of pollution and plummeting temperatures, while cold wave and fog conditions persist in Punjab and Haryana. Snowfall and cold wave alerts have been issued for Uttarakhand and Himachal Pradesh, with rising cold also being felt in Uttar Pradesh and Bihar.