Delhi had anticipated the season's worst pollution levels on the morning after Diwali, but the air quality, although "very poor", turned out better than the last three years, according to data of the government's air quality monitors. The Ministry of Earth Sciences' air quality monitoring service, SAFAR, had earlier predicted that the city's overall air quality index (AQI) would enter the "severe" category between 1 am and 6 am on Monday, primarily due to firecracker emissions, unfavourable weather and a significant spike in stubble burning.