New Delhi, Dec 24 (IANS): The overall Delhi air quality index (AQI) on Tuesday was in the "very poor" category with a count of 353 and is expected to deteriorate further.

According to Safar India, the AQI is likely to deteriorate to the higher end of very poor by Tuesday night. The Safar India model suggests a slight improvement in wind speed and ventilation by Wednesday.

A marginal improvement in AQI is forecast for December 25-26 December but within the "very poor" category only. From December 27 onwards, winds are forecast to slow down for three days and the same day, AQI is forecast to deteriorate towards the higher end of the "very poor" category.

The dense fog in the morning hours is likely to continue for the next two days under favorable meteorological conditions. As per the Safar model, Wednesday's top 3 air pollution hot spots are likely to be Jahangirpuri, Vasundhara and Sahibabad.

Low surface wind speed and low ventilation are forecast for an extended period from December 27 and likely to lead to the accumulation of pollutants. By December 29, AQI is likely to touch higher levels.