New Delhi: The dense fog has caused significant disruptions to train schedules across Northern India, with several trains running late by hours. Passengers are facing delays as visibility issues continue to impact railway operations. The situation is particularly challenging during the peak winter season when fog regularly hampers transportation. As per Indian Railways, the Unchahar Express (14217) has been delayed by 215 minutes as of 6:00 AM on Friday, causing major inconvenience to passengers. Similarly, the Kaifiyat Express (12225) is running late by 178 minutes. The Prayagraj Express (12418), another key train on the route, is delayed by 110 minutes, while the Vikramshila Express (12367) has been held back by 119 minutes. Other significant delays include the AP Express (20805), which is running late by 240 minutes, and the RKMP NZM SF Express (12155), delayed by 109 minutes. Meanwhile, the air quality in the national capital continued in the ‘poor’ category. According to the Central Pollution Control Board, the AQI was recorded at 294 in Delhi today at 7 am. Delhi Pollution Control Committee (DPCC), Mundka recorded an AQI of 324, Narela reached 320, Nehru Nagar hit 360, and Patparganj registered an AQI of 377. Additionally, Okhla Phase-2 reported an AQI of 351, while Sonia Vihar stood at 323. Notably, Vivek Vihar had the highest reading at 390. Other areas like R K Puram (344), Rohini (343), and Najafgarh (221) also exhibited unhealthy air quality. However, data from Punjabi Bagh remained insufficient in the last 24 hours. Meanwhile, areas such as Mandir Marg (144) and Sri Aurobindo Marg (156) showed relatively lower but still moderate AQI levels. An 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.