Delhi AQI is likely to remain in the “poor” category on Monday and Tuesday, and may further deteriorate to the “very poor” category by Wednesday. As the temperature dropped to 18℃ on 1 November, Delhi's air quality plummeted into the 'poor' category, undoing the brief respite brought by last week's rains.Typically, low temperatures and fog slow down dispersion by trapping pollutants near the surface.