New Delhi/ Srinagar, Dec 21 (ANI): Northern India grappled with extreme cold as the mercury dipped further on Sunday. People in New Delhi sat around bonfire to keep them warm and sipped cups of tea. On the other hand, Chilai Kalan - the harshest 40-day period of winter - arrived in Jammu and Kashmir with upper reaches of the valley receiving fresh snowfall. The cold wave has added to the troubles of daily wage labourers like auto drivers and rickshaw pullers and homeless people as they have no alternative but to bear the chill and earn their living. The sudden dip in temperatures is said to have been caused by snowfall in the Himalayas and has adversely impacted the upper half of the country. Meanwhile, minimum temperatures in Jammu and Kashmir have dropped to sub-zero level. People are busy preparing and stocking up for Chilai Kalan. Reportedly, this year Chilai Kalan has arrived earlier than expected, sparking fears that temperatures may dip lower than the average.