Last Updated:December 17, 2025, 21:00 IST Dehradun’s real-time AQI on Wednesday hovered between 260 and 300, worsening significantly after sunset. Data from the Central Pollution Control Board showed that by 4 pm on Wednesday, Dehradun’s AQI stood at 294. Dehradun’s air quality deteriorated over the past two days, with the Air Quality Index (AQI) slipping into the “poor” category and approaching “severe” levels at night. Dehradun’s real-time AQI on Wednesday hovered between 260 and 300, worsening significantly after sunset. This comes as Delhi continued to grapple with ‘very poor’ air quality, recording an AQI of 328 on Wednesday morning despite a slight improvement from 377 a day earlier, with smog and fog reducing visibility across large parts of the national capital. Dehradun Air Quality Deteriorates Sharply After Sunset Professor Vijay Shridhar, who heads the pollution monitoring centre at Doon University, told news agency PTI that the city’s average AQI touched 291 during the day, placing it in a grey zone between “polluted” and “severely polluted”. “There is some improvement during daylight hours because of air …