Cloudy sky with light rain predicted in Delhi, air quality improves
Delhi is likely to see a generally cloudy sky with light rain and thundershowers on Monday according to the India Meteorological Department’s (IMD) forecast. The minimum temperature in the city on Monday is likely to be at 20 degrees Celsius while the maximum temperature is predicted to reach 29 degrees Celsius. The minimum temperature on Sunday was 23.5 degrees Celsius, four notches above normal, while the maximum temperature was 30.4 degrees Celsius -- two degrees below normal.
Sunday’s rainfall has led to improvement in Delhi’s air quality, which was in the “satisfactory” category on Monday morning with 94 AQI or air quality index at 7am, according to the Central Pollution Control Board (CPCB). On Sunday, the average 24-hour AQI in the national capital was 298, at the higher-end of the “poor” category. The prominent pollutant was PM2.5-- particles that have diameter less than 2.5 micrometres.
An AQI between zero and 50 is considered ‘good’, 51 and 100 ‘satisfactory’, 101 and 200 ‘moderate’, 201 and 300 ‘poor’, 301 and 400 ‘very poor’, and 401 and 500 ‘severe’.
On Sunday, the Union ministry of earth science’s air quality monitoring centre, the System of Air Quality and Weather Forecasting and Research (Safar) said, “Delhi’s AQI is in the very poor category with PM2.5 as the lead pollutant. Lower wind speed and low mixing layer height were inhibiting dispersion along with moderate stubble intrusion. However, now that wind direction is mainly from the eastern side and moderate rain is expected, AQI will improve significantly and touch moderate category for tomorrow and then again degrade to poor category for the next 2 days. The SAFAR effective fire count was observed as 815 but as winds were not favourable and rain was expected, the stubble contribution today was likely to be just 2%, which is down from 14% yesterday.”
According to Safar, the local wind speed will be the factor determining the city’s air quality. The local wind speed and ventilation is in moderate category while there is no external dust intrusion in Delhi’s air.