Delhi on Monday recorded its coldest day of the month so far as the minimum temperature dropped to 5.3 degrees Celsius, two notches below the season's average and almost the same as the hill station of Nainital, according to the India Meteorological Department (IMD).
Nainital recorded a low of 5.4 degrees Celsius, the IMD website showed.
On December 15 last year, the national capital recorded its lowest minimum temperature of the season so far at 4.9 degrees, four notches below the season's average.
Delhi recorded a maximum temperature of 17.5 degrees Celsius, a notch below the season's average, on Monday.
The humidity levels oscillated between 84 per cent and 100 per cent.
"Cold day to severe cold day conditions are very likely to persist in some parts of Delhi on Tuesday and abate thereafter," an IMD official said.
The weather department has forecast a generally cloudy sky for Tuesday with a possibility of light rain or drizzle. The maximum and minimum temperatures are likely to settle around 15 degrees Celsius and 7 degrees Celsius, respectively.
According to the Railways, 20 Delhi-bound trains were delayed due to weather-related conditions.
Delhi's 24-hour average Air Quality Index (AQI) stood at 345, in the 'very poor' category, at 4 pm.
An AQI between zero and 50 is considered 'good', 51 and 100 'satisfactory', 101 and 200 'moderate', 201 and 300 'poor', 301 and 400 'very poor', and 401 and 500 'severe'.