New Delhi, Jan 2 : Residents of Delhi on Tuesday encountered shallow fog, but according to the India Meteorological Department (IMD), there is no anticipated fog in the forecast for the next 12 hours. The minimum temperature in the national capital on Tuesday was recorder at 8.3 degrees Celsius, while the maximum is expected at about 17 degrees, the IMD said. As of 8.30 a.m., visibility at Palam stood at 1,200 meters, while Safdarjung recorded 500 meters. The weatherman said there were signs of improvement in visibility conditions, suggesting a gradual easing of the dense 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. Meanwhile, the departure and arrival times of trains have been affected. Several trains arriving in the Delhi region were dealing with delays, causing frustration among passengers. At least 26 trains are behind their scheduled arrival time, and the extent of delay varies across multiple routes. The highest delay reported in trains arriving in Delhi is six hours. While the Bhopal to Nizamuddin train has been delayed by four hours and 30 minutes, passengers of the Bhubaneshwar-New Delhi Rajdhani have also urged to check updated schedules due to a five-hour delay Meanwhile, the air quality continued to remain in 'very poor' category at several stations across the city. The AQI scale categorises levels from 0 to 500, with Anand Vihar breaching the 'severe' threshold. At the Anand Vihar area, PM2.5 levels remained into the 'very poor' category standing at 380 and PM10 reached 319, 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'. However, the Indira Gandhi International Airport T3 witnessed PM2.5 levels at 275 and PM10 at 195, falling under the 'poor' and 'moderate' category, respectively. The CO level was recorded at 60, maintaining a 'satisfactory' rating. /IANS