Dense fog blankets Delhi, AQI stays in 'very poor' category

Delhi woke up shrouded in fog on Wednesday morning, with little visibility and 'very poor' air. The India Meteorological Department (IMD) issued an orange alert for dense fog between 8.30 am and 10 am.

Visibility was recorded at 50 metres at both Palam and Safdarjung at 6.30 am, the weather office said.

The national capital recorded a 24-hour average Air Quality Index (AQI) of 384, according to data from the Central Pollution Control Board (CPCB).

A station-wise breakdown showed that 21 monitoring stations recorded 'very poor' air quality, while 16 stations were in the 'severe' category, with Anand Vihar registering the worst AQI at 452, according to data from the CPCB's SAMEER app.

According to CPCB classification, an AQI between 0 and 50 is considered 'good', 51 to 100 'satisfactory', 101 to 200 'moderate', 201 to 300 'poor', 301 to 400 'very poor', and 401 to 500 'severe'.

The air quality outlook remains grim, the Air Quality Early Warning System said, with the AQI likely to deteriorate to the 'severe' category on January 1, before letting up to the 'very poor' category on January 2. For the subsequent six days, air quality is expected to remain 'very poor', it said.

Officials attributed the poor air to an unfavourable ventilation index of below 6,000 square metres per second and average wind speeds of less than 10 kmph, which are not conducive to the dispersion of pollutants. On Tuesday, the AQI stood at 388, marking a marginal improvement from Monday, when the city recorded a 'severe' reading of 401.

On Wednesday, the IMD said the minimum temperature at Safdarjung and Ayanagar was recorded at 6.4 degrees Celsius, 0.4 degrees Celsius below normal.

The maximum temperature is expected to be around 23 degrees Celsius. Dense fog is likely to persist through the day. Palam station logged a minimum of 7.7 degrees Celsius, Lodhi Road 6.8 degrees Celsius, and the Ridge 7.8 degrees Celsius, according to the IMD.

On New Year's Day, the weather office has forecast a generally cloudy sky with light rain over the national capital.