New Delhi, Feb 13 (IANS): The air quality index (AQI) in Delhi was in the 'very poor' category on Friday with a reading of 331. According to Safar India, the overall Delhi air quality is in the lower end of the very poor category as forecasted.

"Surface winds are low and they are likely to marginally improve during day time. The ventilation is likely to stay in the same range and no significant change in AQI is expected in the next couple of days," the System of Air Quality and Weather Forecasting and Research (Safar) India said.

"AQI is likely to stay in the very poor category for the next two days. It is likely to marginally improve to the lower end of very poor to poor category on February 15," it added.

The US Embassy in Delhi showed an AQI reading of 313 in the hazardous category. The Central Pollution Control Board (CPCB) AQI reading was at 366 in the very poor category.

Surprisingly, Mumbai was also in the very poor category of AQI on Friday with a reading of 301.