Strong north-westerly winds intensified the cold wave sweeping Bihar with the State capital recording a minimum temperature of 7.7 degrees Celsius on Monday forcing the Patna district administration to announce closure of all schools till Tuesday. Met office said the north-westerly wind had plummeted the mercury throughout the State. Thick fog also engulfed major parts of it. While Gaya recorded 6.1 degrees Celsius, Bhagalpur and Purnea had 10.2 degrees and 10.2 degrees. The met office said the minimum temperature was likely to fall further and foggy conditions would continue for a few more days. New Delhi: Cold wave intensified in Jammu and Kashmir on Monday while fog covered parts of Punjab, Haryana and Chandigarh though there was some respite from biting cold in Rajasthan with rise in mercury level. As many as 425 people have lost their lives due to cold in North India this winter. A thick blanket of fog covered parts of Punjab, Haryana and Chandigarh for the second consecutive day on Monday.