Severe cold wave conditions were observed in parts of Haryana, Punjab, Rajasthan and Himachal Pradesh, the India Meteorological Department said on Sunday.
The MeT office also said cold wave swept parts of Delhi, Uttar Pradesh, Madhya Pradesh, Jammu and Kashmir, Ladakh, Gilgit-Baltistan and Muzaffarabad, Uttarakhand and Himachal Pradesh.
Churu in Rajasthan reported the lowest minimum temperature of minus 2.6 degrees Celsius in northwest India followed by Sikar (minus 2.5 degrees Celsius) and Amritsar (minus 0.5 degree Celsius), the IMD said.
The Safdarjung Observatory, which provides representative data for Delhi, recorded a minimum temperature of 4.6 degrees Celsius, three notches below normal and the lowest this season so far. The weather station at Lodhi Road recorded a low of 3.6 degrees Celsius.
Some parts of Uttarakhand reported dense fog.
The India Meteorological Department (IMD) predicted that cold wave to severe cold wave conditions are very likely to continue in northwest India over the next three days and abate thereafter.
Dense fog is predicted in a few regions of Uttarakhand over the next two days and in Punjab and Haryana on December 23 and 24, it said.
Cold and dry northwesterly winds, gusting up to 15 kmph, are likely to continue over the plains of northwest India till Tuesday, 'enhancing the adverse impact of cold wave and cold day conditions', the weather office said.
According to IMD, 'very dense' fog is when visibility is between 0 and 50 metres, 51 and 200 is 'dense', 201 and 500 'moderate', and 501 and 1,000 metres 'shallow'.
In the plains, the IMD declares a cold wave if the minimum temperature dips to 4 degrees Celsius.
A cold wave is also declared when the minimum temperature is 10 degrees Celsius or below and is 4.5 notches less than normal.
A 'severe' cold wave is when the minimum temperature dips to two degrees Celsius or the departure from normal is more than 6.4 degrees Celsius.
When the minimum temperature is less than or equal to 10 degrees Celsius and the maximum temperature is at least 4.5 degrees Celsius below the normal, it is said to be a 'cold day'.
