The air quality in Delhi improved marginally on Friday, largely due to a slight increase in wind speed, but was still hovering in the 'very poor' category.
According to the Centre-run System of Air Quality and Weather Forecasting And Research (SAFAR), the Air Quality Index of the capital in the morning was recorded at 306, falling in the lower end of the 'very poor' category.
The AQI between the range of 51 to 100 is considered as satisfactory, 101-200 is moderate, 201-300 falls under the category of poor. While 300-400 is considered as 'very poor', levels between 401-500 fall under the 'hazardous category'.
According to Safar, "major cause of deterioration at present is gradual change in weather conditions (slowing surface winds, lowering BLH, cooling) towards unfavourable side. The stubble burning activity in Haryana, Panjab, and nearby border regions are moderate but has shown an increasing trend over the last 72 hours. Additionally, few new fires are observed over western Uttar Pradesh."
For the rest of the day, SAFAR predicted a marginal improvement in air quality.
"Under the influence of approaching western disturbance, a slight increase in wind speed is expected for Friday only. Under this condition, a marginal improvement in Delhi's AQ is forecasted for Friday in the lower end of very poor to upper end of the poor category," SAFAR said.
"Thereafter by October 19, faster deterioration in air quality to the middle of the very poor category is forecasted as there is high probability of significant stubble intrusion," it said.