<span style="color: #222222;">Delhi's air quality dropped just ahead of Diwali today. Several areas in Delhi recorded poor to very poor air quality. According to the Central Pollution Control Board (CPCB) data, the city's overall Air Quality Index (AQI) fluctuated between 123.5 to 253 micrograms per cubic metre in the morning hours.</span><br />'' <span style="color: #222222;"><br />'' Delhi's air quality had dropped to season's worst yesterday, with the decreased wind speed leading to accumulation of pollutants and affecting dispersion.</span><br />'' <span style="color: #222222;">   <br />'' The Ministry of Earth Sciences' air quality forecast and research service, SAFAR, said, the overall air quality is in the very poor category.<br />'' A sharp deterioration of air quality, to the higher end of the very poor category, is likely today.</span><br />'' <span style="color: #222222;"><br />'' In its Diwali forecast, the System of Air Quality and Weather Forecasting and Research (SAFAR) said, the highest impact of fire-cracker emissions is expected from 1 AM to 6 AM on Monday.</span><br />'' <span style="color: #222222;"><br />'' The impact of stubble burning is expected to be moderate and, if no additional emissions due to firecrackers occur, then the air quality would remain in the middle range of very poor category tomorrow.</span><br />''