Delhi AQI improves to ‘poor’, slight rise in temperatures as fog reduces

Delhi’s air quality index (AQI) improved to the ‘poor’ category on Monday, dipping below the 300 mark for the first time since late last month, data from the Central Pollution Control Board (CPCB) showed. Delhi’s average AQI stood at 285 (poor) at 9am, the lowest since October 29, when it was 268 (poor).
A return of strong, consistent winds from late Saturday evening, gusting to 10-15 kmhr, helped disperse the pollution on Sunday. At the same time, the intensity of fog has reduced in the region, leading to a marginal rise in both maximum and minimum temperatures.
Delhi reported shallow fog on Monday morning, with the lowest visibility of 900m recorded at Safdarjung. The minimum temperature stood at 14°C, which was two degrees above normal. It was 12°C on Sunday. The maximum, which was 29.1°C on Sunday at two degrees above normal, is meanwhile expected to hover around 28°C today.
Although northwesterly winds were persisting in the capital, the maximum and minimum temperatures were over the normal levels. The lowest minimum temperature recorded so far this season is 10.2°C, on November 21. The lowest maximum is 23.5°C on November 18.
CPCB data showed that out of Delhi’s 38 stations online, 15 were in the ‘very poor’ category, with the rest all in ‘poor’. One station — Lodhi Road — was ‘satisfactory’ with an AQI of 95, the data showed.
The CPCB classifies AQI between 0 and 50 as “good”, between 51 and 100 as “satisfactory”, between 101 and 200 as “moderate”, between 201 and 300 as “poor”, between 301 and 400 as “very poor”, and over 400 as “severe”.
Saturday was Delhi’s eighth severe day of this winter season. The first such day was recorded on November 13, with the AQI touching 494 on November 18 — the joint second highest ever in the capital.
“A western disturbance was influencing northwest India, which led to almost calm winds conditions on Saturday. Late towards the night and in the early hours of Sunday, we began to see the impact of this western disturbance weaken and a subsequent increase in wind speeds again. On Sunday, during the day, winds touched 15km/hr, which led to a significant improvement in AQI,” said Mahesh Palawat, vice president at Skymet meteorology, forecasting wind speed to remain consistent on Monday and Tuesday.
Forecasts by the Centre’s Early Warning System for Delhi (EWS) showed that AQI is expected to gradually return to very poor on Monday, with it remaining over 300 on Tuesday too.