According to the National Weather Forecasting Centre of the India Meteorological Department (IMD):
Wind Pattern and Ventilation Index Forecast
Air mass inflow forecast in Delhi along with predicted ventilation coefficient and weather forecast is as follows:
- The air quality over Delhi-NCT is likely to remain in Moderate to Poor category on 23.06.2021 and Poor category on 24.06.2021. PM10 will be the predominant pollutant owing to strong surface winds favourable for raising dust concentration locally and transport of dust from arid regions. The air quality is likely to improve marginally but remain in Poor to Moderate category on 25.06.2021. The Outlook for subsequent 5 Days: The air quality is likely to remain largely in Satisfactory to Moderate category.
- The predominant surface wind is likely to be coming from North directions of Delhi with wind speed 05-12 kmph and partly cloudy sky on 23.06.2021. The predominant surface wind is likely to be coming from Northwest directions of Delhi with wind speed 10-20 kmph, partly cloudy sky and strong surface winds (speed 20-30 kmph) during the day on 24.06.2021.The predominant surface wind is likely to be coming from West- Northwest directions of Delhi with wind speed 12-20 kmph and partly cloudy sky with very light rain/thundershowers on 25.06.2021.
- Predicted maximum mixing depth is likely to be approx. 4400 m on 23.06.2021, 4600 m on 24.06.2021 and 3700 m on 25.06.2021 over Delhi. Maximum Ventilation index is likely to be approx 20000 m2/s on 23.06.2021, 37500 m2/s on 24.06.2021 and 31500 m2/s on 25.06.2021. The ventilation index lower than 6000 m2/s with average wind speed less than 10 kmph is unfavourable or dispersion of pollutants.
- Detailed forecast analysis and verification can be seen at https://ews.tropmet.res.in.