Cold wave and ground frost conditions over some parts of northwest India during the next three days are likely to keep air quality in the national capital "very poor" and could also cause a dip in the minimum temperatures.
"Cold wave and severe cold wave conditions would continue to prevail over Punjab, Haryana and Rajasthan during the next three days and are very likely to extend to isolated places over Delhi and west Uttar Pradesh," the India Meteorological Department (IMD) said in its forecast on Wednesday.
It said that night temperatures in Delhi fell by 2-3 degrees Celsius. The maximum and minimum temperature on Wednesday was recorded at 22 and 5 degrees Celsius, respectively, and are likely to remain at the same levels on Thursday as well.
"The sky on Thursday will be mainly clear with some shallow fog in the morning. However, the minimum temperature on Thursday may fall to 4 degrees Celsius," an IMD official said.
"The minimum temperature is likely to fall in Delhi, resulting in additional moisture in Delhi air, mainly because of cold waves and ground frost conditions over some parts of northwest India during the next three days. Hence, air quality will remain in the very poor zone over the next three days," System of Air Quality and Weather Forecasting and Research (SAFAR) said in its daily forecast.
However, the agency also said that the winds are again becoming partially favourable for the dispersion of pollutants now.
The overall Air Quality Index (AQI) of Delhi at 4 p.m stood at 347 (very poor). In the National Capital Region (NCR), Greater Noida at 366, Ghaziabad at 377, Faridabad at 335 and Noida at 324 also remained in the "very poor" zone.
Meanwhile, Gurugram surprisingly had "satisfactory" air quality with its AQI at just 63 with PM2.5 at 50 microgrammes per cubic metres. It had slipped into the "poor" zone on Tuesday with an AQI of 221 after maintaining days of "moderate" levels of pollution.
As per the data of the Central Pollution Control Board (CPCB), the average concentrations of PM2.5 and PM10 in Delhi at 7 p.m were 224 and 358 microgrammes per cubic metres, respectively. Across NCR, it was between 208 and 348 units.
(With inputs from agencies.)