New Delhi:  It was a misty morning in the national capital on Saturday with the minimum temperature recorded at 15.6 degrees Celsius, while the air quality dipped to "very poor". "The sky will remain clear throughout the day," said an India Meteorological Department official. The maximum temperature was likely to hover around 31 degrees Celsius. The humidity at 8.30 a.m. was 83 per cent. Delhi has been already reeling under "very poor" air quality since the last three days, with an average reading of 342 of PM (particulate matter) 2.5 at 8 a.m. according to Central Pollution Control Board (CPCB). The situation is not set to change any sooner, while it may only get worse towards Diwali, warned CPCB. "Stop any activity level if you experience any unusual coughing, chest discomfort, wheezing, breathing difficulty," said System of Air Quality and Weather Forecasting Research (SAFAR) in its website. With more regions now suffering a "severe or severe-plus" air-quality, the top four most polluted regions in Delhi included Jahangirpuri in north Delhi, Mundaka in west Delhi, Dwarka sub-city in south Delhi and Anand Vihar in east Delhi. Friday's maximum temperature settled at 30.4 degrees Celsius, while the minimum temperature was recorded at 15.8 degrees Celsius, both one notch below the season's average.