Delhi and other northern Indian states and union territories, including Rajasthan and Uttar Pradesh, woke up to freezing cold on Monday with the India Meteorological Department (IMD) predicting the conditions to continue for the next few days.
Temperatures in many states have fallen considerably over the past week, namely in Punjab, Uttar Pradesh, Rajasthan, Haryana, and Delhi.
On Sunday, the mercury dipped to 5.3 degrees Celsius in Delhi, three degrees below normal, while the maximum temperature recorded during the day in the metropolitan city was 16.2 degrees Celsius.
The sharp decline in Delhi's temperature during both day and night made Christmas the coldest day of this winter. But according to the weather office, the mercury in Delhi is set to drop further, with the minimum temperature expected to be 4 degrees Celsius on Monday.
The temperature remained three degrees below normal in Haryana, Punjab, and Rajasthan while a thick blanket of fog covered large parts of these states during the weekend.
Minimum temperatures in these states hovered between 3 and 7 degrees Celsius, affecting the movement of trains and the people on the roads due to low visibility in foggy conditions.
The weather department said these conditions will continue to affect normal life in Haryana, Punjab, Uttar Pradesh, Rajasthan, and Delhi till Tuesday.
Meanwhile, the mercury in Kashmir plunged further as the union territory's capital Srinagar recorded the coldest night of the season on Sunday. At minus 5.8 degrees Celsius, Sunday night turned out to be the coldest in Srinagar, even more chilly than the -5.5 degrees registered on Thursday.
Chillai Kalan, a 40-day period that includes the harshest winter period in Kashmir, began with freezing temperatures on Wednesday.
The region's MeT department, however, was hopeful of some respite from bone-chilling cold from December 26 onwards.