New Delhi, Dec 17 (IANS): Delhi-NCR residents woke up to a mainly clear sky on Friday with the maximum and minimum temperature being recorded at 20 and 8 degrees Celsius, respectively, while the relative humidity at 8.30 a.m. stood at 77 per cent, according to the India Meteorological Department (IMD).

The IMD in its Thursday forecast said that due to a western disturbance, the maximum temperature this Christmas will be colder with light to moderate rain or snowfall over the western Himalayan region, northwest and adjoining areas of central India.

Meanwhile, Delhi's air quality continues to settle in the 'very poor' category, with the System of Air Quality and Weather Forecasting and Research's (SAFAR) recording the Air Quality Index (AQI) at 339 at 9.30 a.m.

The level of PM10 and PM2.5 pollutants in the air was recorded in the 'poor' (283) and 'very poor' (171) categories, respectively.

"As per the air quality and weather bulletin for Delhi-NCR, the air quality over Delhi-NCT is likely to improve and remain in the lower end of very poor category on December 17 and poor category on December 18 and 19. The outlook for the subsequent five days: The air quality is likely to improve significantly and remain in the poor category."