The India Meteorological Department (IMD) has provided an explanation for the unusually low daytime temperatures being experienced in Delhi and other parts of North India. According to IMD scientist Naresh Kumar, a complete layer of dense fog and clouds is preventing direct sunlight from reaching the Earth's surface, leading to a dip in daytime temperatures. This phenomenon has resulted in the issuance of a yellow alert for 'cold day' conditions across several states, including Punjab, Haryana, Uttar Pradesh, and Bihar, with the alert expected to last for a few days. The IMD has also predicted dense to very dense fog, further exacerbating the cold conditions. In Delhi, specific weather stations like Palam and Lodhi Road have recorded 'cold day' conditions, where the maximum temperature departure from normal is significant. This is compounded by icy-cold northwesterly winds that are contributing to the biting chill. Experts anticipate these cold conditions to intensify and persist in North India until around January 15. Alongside the low temperatures and fog, Delhi's air quality remains a significant concern, with the Air Quality Index (AQI) frequently falling into the 'poor' and 'very poor' categories, sometimes even reaching 'severe' levels. The combination of cold, fog, and poor air quality poses health risks, prompting advisories for residents to take necessary precautions. The article also notes that while minimum temperatures are remaining low, they may not reach the extreme lows seen in previous years, but the overall cold wave is expected to continue.