New Delhi, Jan 9 : Delhi and its adjoining areas woke up to a cold and foggy morning on Tuesday with a minimum temperature of 7.9 degrees Celsius, one notch above the seasonal average, and some areas witnessing a surprising drizzle, according to India Meteorological Department (IMD). The IMD further predicted that the maximum temperature is likely to hover around 17 degree Celsius on Tuesday with partly cloudy sky. The city recorded lowest visibility of 500 m at Safdarjung at 8 a.m. while Palam recorded 300 m at 5 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 16 trains were running late by hours due to fog and cold wave. The Air quality continued to remain in the 'very poor' category at several stations across the city. At the Anand Vihar area, PM2.5 levels remained into the 'very poor' category standing at 354 and PM10 reached 243 or 'moderate'. The CO was at 129 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'. The Indira Gandhi International (IGI) Airport T3 also witnessed PM2.5 levels at 320, the 'very poor' category while the PM10 was at 177, falling under the 'moderate' category, respectively. /IANS