Delhi's air quality index at 8 am on Thursday was 339. (File)
Delhi's air quality improved to the "poor" category on Thursday due to intermittent rains while the city's maximum temperature settled at 21.1 degrees Celsius, two notches above the season's average.
The 24-hour air quality index (AQI) of Delhi read 258 at 4 pm on Thursday, according to Central Pollution Control Board (CPCB) data.
The AQIs of its neighbouring cities -- Faridabad (219), Noida (252), Gurugram (224) -- were also recorded in the "poor" category.
However, the AQI in Greater Noida (182) and Ghaziabad (179) was recorded in the "moderate" category.
The national capital's AQI at 8 am on Thursday was 339, which falls in the "very poor" category.
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".
"The AQI has improved today (Thursday) to 'poor' category due to yesterday's intermittent rain spells causing wet deposition of particulate matter. On January 8, it is likely to rain with high wind speeds leading to improvement in AQI due to wet deposition and strong dispersion resulting AQI to be in 'lower end of poor' or 'moderate' category," the System of Air Quality and Weather Forecasting and Research (SAFAR) said.
It predicted that January 9 onwards, the air quality is likely to worsen due to gradual decrease in maximum and minimum temperatures as well as wind speed, all contributing to low dispersion of pollutants.
The national capital witnessed a cloudy morning on Thursday and recorded minimum temperature at 11.7 degrees Celsius, five notches above the season's average.
The day's maximum temperature settled at 21.1 degrees Celsius, two notches above the season's average, the India Meteorological Department (IMD) said.
"It will be generally cloudy sky with light rain or drizzle on Friday. The maximum and minimum temperatures are likely to hover around 21 degrees Celsius and 12 degrees Celsius respectively on Friday," the weather office predicted.
The IMD said the city received 9 mm of rainfall in the last 24 hours between 8.30 am on Wednesday to 8.30 am on Thursday.
The relative humidity at 5.30 pm was 71 per cent in Delhi, IMD said.
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