Delhi on Saturday recorded a minimum temperature of six degrees Celsius, the lowest so far this winter, PTI reported.

The temperature was recorded at the Safdarjung observatory, which provides representatives figures for the city. The observatories at Ridge and Ayanagar recorded a minimum temperature of 5 degrees Celsius, according to ANI.

Delhi’s minimum temperature was two degrees below the season’s average, the India Meteorological Department said.

The weather department has predicted cold wave conditions in Delhi, Punjab, Haryana, Chandigarh and the northern parts of Rajasthan, Madhya Pradesh and Uttar Pradesh till December 21. The weather department’s Director General Mrutyunjay Mohapatra told ANI that minimum temperatures are expected to rise slightly after that.

The weather department declares a “cold wave” in the plains when the temperature remains less than 10 degrees Celsius and 4.5 degrees to 6.4 degrees below the normal temperature.

Meanwhile, at 4 pm on Saturday, Delhi’s air quality index was at 227, which falls in the “poor” category.