New Delhi, Jan 6 : Moderate fog enveloped Delhi on Saturday morning, accompanied by a minimum temperature of 8.9 degrees Celsius, which is two notches above the season’s average, as reported by the India Meteorological Department (IMD). Visibility at Safdarjung, Delhi’s primary weather station, and Palam was measured at 500 meters at 5:30 am, according to the IMD. The relative humidity reached 100 per cent at 8:30 am. Fog-related disruptions affected train services, resulting in delays for 14 Delhi-bound trains, as per officials. At 9 am, Delhi’s Air Quality Index (AQI) was recorded at 315, falling within the ‘very poor’ category, according to Central Pollution Control Board data. The AQI scale categorizes air quality as ‘good’ (0-50), ‘satisfactory’ (51-100), ‘moderate’ (101-200), ‘poor’ (201-300), ‘very poor’ (301-400), and ‘severe’ (401-500).