A cold wave swept Delhi on Sunday as it recorded the coldest morning of the season so far at 3.4 degrees Celsius, the India Meteorological Department (IMD) said.
On Saturday, the minimum temperature at the Safdarjung Observatory, which provides representative data for the city, had settled at 3.9 degrees Celsius.
"The observatory recorded a minimum of 3.4 degrees Celsius, five notches below the normal, on Sunday morning. The maximum temperature is likely to settle around 22 degrees Celsius," an IMD official said.
The mercury dipped to 3.3 degrees Celsius at Lodhi Road, as icy winds from snow-laden Western Himalayas barrelled through the city, the IMD said.
On Friday, the minimum temperature had plunged to 2.7 degrees Celsius at Jafarpur.
The city had recorded a "severe" cold day on Thursday as the maximum temperature dropped to 15.2 degrees Celsius, seven notches below normal and the lowest this season so far. However, it rose to 19.8 degrees Celsius on Friday and 21.8 degrees Celsius on Saturday.
According to the IMD, a "cold day" is when the minimum temperature is less than 10 degrees Celsius and the maximum is at least 4.4 degrees Celsius below the normal. A "severe" cold day is when the maximum temperature is at least 6.5 notches below the normal.
For the plains, the IMD declares a cold wave when the minimum temperature is 10 degrees Celsius or below and is 4.5 notches less than the normal for two consecutive days.
However, for small areas such as Delhi, a cold wave can be declared if the criteria is fulfilled even for a day, officials said.
The minimum temperature is expected to hover around 5 degrees Celsius in the next five to six days, it said.