Delhi recorded its lowest minimum temperature of October so far on Monday, with Safdarjung registering 17.1 degrees Celsius, 1.3 degrees below normal. The city's average AQI stood at 139, in the moderate category, but forecasts warned of poor air quality from October 21. Pusa recorded the worst reading at 281.

Delhi recorded its lowest minimum temperature of October so far on Monday, with the mercury dropping to 17.1 degrees Celsius at the Safdarjung weather station. However, the cooler weather brought little relief from pollution, with forecasts warning that the city's air quality could deteriorate to the 'poor' category from October 21. The India Meteorological Department (IMD) said the minimum temperature was 1.3 degrees below the seasonal average. The maximum temperature during the day reached 31.7 degrees Celsius. An IMD official confirmed that Monday's reading marked the coldest night temperature recorded in the capital this month so far.

Delhi AQI remains moderate, Pusa records 281

According to the Central Pollution Control Board (CPCB), Delhi's 24-hour average Air Quality Index (AQI) stood at 139 at 4 pm on Monday, placing it in the 'moderate' category.

Of the 58 monitoring stations reporting data, two recorded 'poor' air quality, six were in the 'satisfactory' category, while the remaining stations reported 'moderate' levels. Pusa recorded the highest AQI at 281, placing it in the 'poor' category.

The Air Quality Early Warning System has forecast that Delhi's air quality will remain 'moderate' on October 19 and 20 before slipping into the 'poor' category on October 21 and 22. The outlook for the following six days also points to poor air quality.

The system warned that unfavourable weather conditions could prevent pollutants from dispersing effectively. A ventilation index below 6,000 square metres per second, combined with average wind speeds below 10 kmph, is considered unfavourable for pollution dispersion.

98 farm fires detected across six states

Meanwhile, satellite data recorded 98 stubble-burning incidents across six states on October 19, according to the CREAMS laboratory at the ICAR-Indian Agricultural Research Institute.

Uttar Pradesh reported 27 incidents, followed by Punjab with 25, Rajasthan with 24, Uttarakhand with 18 and Madhya Pradesh with four. No farm-fire events were detected in Haryana or Delhi on Monday.

Between September 15 and October 19, a total of 1,171 farm-fire incidents were recorded across the six states. Madhya Pradesh accounted for 370, followed by Punjab with 368, Rajasthan with 197, Uttar Pradesh with 175, Uttarakhand with 51, Haryana with nine and Delhi with one.

How AQI categories are classified

The CPCB classifies AQI readings of 0-50 as 'good', 51-100 as 'satisfactory', 101-200 as 'moderate', 201-300 as 'poor', 301-400 as 'very poor' and 401-500 as 'severe'.

With temperatures falling and pollution levels expected to rise, Delhi faces the prospect of cooler mornings alongside deteriorating air quality in the coming days.

(With inputs from agencies)