On Friday, a blanket of fog enveloped the Indo-Gangetic plains, extending into the northeast region and causing a significant drop in visibility and disruptions to rail operations. Railways spokesperson reported that the schedules of “23 trains arriving in Delhi” were affected due to the dense fog. Satellite imagery indicated the presence of fog and low-level clouds over Punjab, Haryana, Delhi, Uttar Pradesh, Bihar, and extending towards northeast India, with patches of fog observed over Odisha. According to the India Meteorological Department (IMD), visibility levels plummeted to zero at Delhi’s Palam observatory near the Indira Gandhi International Airport, while Safdarjung Airport witnessed visibility up to 200 meters.
Several regions experienced severely reduced visibility, with readings of 25 meters in Amritsar (Punjab), Lucknow, and Varanasi (Uttar Pradesh), 50 meters in Chandigarh, Bareilly (Uttar Pradesh), Purnia (Bihar), and Tezpur (Assam), and 200 meters in Ambala (Haryana) and Ganganagar (Rajasthan). The IMD classifies visibility conditions as very dense fog (0-50 meters), dense fog (51-200 meters), moderate fog (201-500 meters), and shallow fog (501-1,000 meters). The IMD forecasted the likelihood of dense to very dense fog during morning hours in parts of northwest India over the next five days. Despite some relief on Wednesday and Thursday as sunlight penetrated the thinned fog layer, cold winds persisted, maintaining cold-day to severe cold-day conditions in many parts of northern India since December 30-31.