The national capital's air quality on Thursday continued to remain in the poor category due to favourable winds, even as the city witnessed the lowest minimum temperature of the month so far at 8.4 degrees Celsius, weather office said.

The air quality index (AQI) in the city stood at 261 at 8 am. Neighbouring Faridabad (237), Ghaziabad (266), Greater Noida (264), Gurgaon (241) and Noida (235) also recorded air quality in 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 city's 24-hour average AQI on Wednesday was 237 at 4 pm.

The Ministry of Earth Sciences' air quality forecast agency SAFAR said the improvement in the air quality was "higher than expected, implying that (air pollution) control measures are yielding results".

Moderate wind speed is likely to increase ventilation over the next four days, it said.

Delhi's minimum temperature was recorded at 8.4 degrees Celsius, one notch below the normal, which is lowest in the month so far, the India Meteorological Department (IMD) said.

The weather office predicted shallow fog in the day and it said that the maximum temperature of the day is likely to hover around 24 degrees Celsius.

The relative humidity at 8.30 am was 92 per cent, the weather office said.

The minimum temperature on Wednesday was recorded at 10.1 degrees Celsius, a notch above the normal. The maximum temperature on Wednesday settled at 24 degrees Celsius, weather office said.