With most days bitterly chilly and sunless due to fog this month, Delhi experienced its coldest Jan in 21 years in terms of day temperatures. The mean maximum temperature during the month at Safdarjung was 17.9 degrees Celsius, the same as in 2015 and the lowest since 2003.This was only the third instance in records going back 33 years that the mean maximum temperature in Jan had stayed below 18 degrees C, as per IMD data.