Delhi records cleanest air day since last October, average AQI of 135

Delhi on Monday logged a 24-hour average AQI of 135, the lowest since October 13 last year, owing to chilly winds that swept through the city dispersing the pollutants.

The cold northwesterly winds -- blowing up to a speed of 48 kmph -- from the mountainous regions led to a drop in temperatures.

The city recorded a high of 23.2 degrees Celsius, normal for this time of the year and a minimum temperature of 8.7 degrees Celsius, two notches below the season's average.

Humidity level during the day oscillated between 25 per cent and 62 per cent.

The weather department has forecast a mainly clear sky with strong surface winds and occasional gusty winds for Tuesday. The maximum and minimum temperatures are likely to settle around 26 degrees Celsius and 12 degrees Celsius respectively on Tuesday.

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.

According to the Ministry of Earth Sciences' air quality monitor SAFAR, the air quality in the city over the next three days is likely to see improvement.

"Air quality is likely to improve but will remain within moderate' or lower end of poor' for the next three days due to enhanced dispersion by strong surface wind speed.

"Upper level winds (around 800 m) are blowing from northwest direction and likely to remain relatively high for next three days that helps dilution of pollution. From February 16 onwards, surface winds are likely to be calm and will weaken dispersion and deteriorate air quality," it said.

The air quality is likely to deteriorate and reach the upper end of the moderate category on February 15 and enter the poor category on February 16, it added.