New Delhi, Jan 7 : The national capital woke up to minimum temperature of 8.2 degrees celsius, one notch above the seasonal average, according to India Meteorological Department (IMD) The IMD further predicted that the maximum temperature is likely to hover around 16 degree Celsius on Sunday. The city recorded lowest visibility of 500 m at Safdarjung at 8 a.m. while the Palam recorded 900 m at 1 a.m. The weather forecast department said that the city witnessed shallow fog. The IMD classifies fog intensity into four types: shallow, moderate, dense and very dense fog. The visibility ranges from 999 m to 500 m, 499 m to 200 m, 199 m to 50 m and less than 50 m, respectively. According to Indian Railways, a total of 22 trains were running late by hours due to fog and cold wave. The air quality continued to remain in 'very poor' category at several stations across the city. At Anand Vihar, PM2.5 levels remained into 'very poor' category standing at 339 and PM10 reached 265 or 'very poor'. The CO was at 115 or 'moderate', according to the Central Pollution Control Board (CPCB). The Air Quality Index (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'. T3 terminal of the Indira Gandhi International (IGI) Airport also witnessed PM2.5 levels at 238, in 'poor' category while PM10 was at 126, falling under the 'moderate' category, respectively. /IANS