Delhi’s air quality worsened on Thursday, November 6, 2025, with multiple areas recording levels in the “very poor” category, according to the Central Pollution Control Board (CPCB). As of 8 am, the air quality index (AQI) for Jahangirpuri stood at 284, while ITO registered 295, indicating a significant rise in pollution levels that blanketed the national capital in a dense layer of smog.

The deterioration was particularly evident in parts of North Delhi, where Mundka recorded an AQI of 305, Rohini stood at 296, and Narela registered 302. The surrounding National Capital Region (NCR) also faced poor air conditions, with Noida’s Sector 62 reporting an AQI of 215 and Ghaziabad’s Sanjay Nagar at 265.

According to the CPCB, air quality is categorised as follows: good (0–50), satisfactory (51–100), moderate (101–200), poor (201–300), very poor (301–400), and severe (above 400). Thursday’s readings placed large swathes of the city in the poor to very poor range, raising concerns about public health, particularly for vulnerable groups such as children, the elderly, and people with respiratory conditions.

AQI Spike After Temporary Improvement

The spike in pollution comes after Delhi saw a brief improvement in air quality on Wednesday. CPCB data showed that the 24-hour average AQI at 4 pm Wednesday was 202 (poor), a sharp drop from 291 (poor) recorded the previous day. By 7 pm, the index had further improved to 197 (moderate). Earlier on Wednesday, AQI readings fluctuated around 221 at 10 am and 215 at 11 am, indicating a short-lived period of better air quality.

However, this temporary respite was followed by a rapid deterioration overnight into Thursday morning. On Tuesday, the AQI had stood at 291, and Monday saw a reading of 309, underscoring a trend of fluctuating air quality levels over the past several days. On Sunday, the capital recorded the worst air quality of the season, with an AQI reading of 388 at 10 am.

Levels of Key Pollutants

The improvement on Wednesday had been attributed to a temporary dip in pollutant levels. PM10, the particulate matter that can penetrate deep into the lungs, had decreased to 175.2 micrograms per cubic metre from 260 a day earlier. PM2.5, the finer particulate matter capable of entering the bloodstream, fell to 85.5 micrograms per cubic metre from 128.2 on Tuesday.

Despite these temporary reductions, pollutant levels surged again on Thursday, with 28 of Delhi’s 38 monitoring stations reporting “very poor” air quality, according to the CPCB’s Sameer app. The rebound in pollution highlights the persistent challenge of managing air quality in the capital, which faces recurring episodes of smog during the winter months.

Historical Context

Delhi has not experienced sustained periods of “good” air for over two years. The last time the city recorded such conditions was in September 2023, when unseasonal rainfall and strong winds helped disperse pollutants. Since then, seasonal trends, including temperature inversion layers, increased vehicular emissions, construction dust, and stubble burning in neighboring states, have contributed to the city’s chronic air pollution issues.

Experts warn that air quality can fluctuate rapidly in the capital, particularly in late October and November, due to a combination of meteorological conditions and human activity. The prevalence of calm winds, low temperatures, and high humidity can trap pollutants near ground level, leading to sudden spikes in AQI.

Health Implications and Advisory

The rise in pollution levels has direct implications for public health. The CPCB advises residents, particularly those in areas recording “very poor” AQI, to limit outdoor activities, wear N95 masks when venturing outside, and ensure proper ventilation indoors. Schools are often urged to monitor outdoor activities, and individuals with respiratory or cardiovascular conditions are advised to take extra precautions.

Authorities continue to monitor air quality and implement short-term measures to reduce pollution. These include restrictions on construction dust, control of vehicular emissions, and public advisories against burning waste or biomass. However, experts emphasise that long-term solutions, such as improving public transport infrastructure, reducing industrial emissions, and addressing stubble burning in surrounding states, are essential for sustained improvement.

Looking Ahead

With the winter season fully setting in, Delhi is expected to face additional challenges in maintaining air quality. Forecasts suggest that smog episodes could recur, especially in the early mornings and evenings, as temperatures drop and wind speeds remain low.

Residents are being urged to stay updated through the CPCB’s real-time monitoring tools, including the Sameer app, and follow government advisories to minimize exposure to harmful air pollutants.

As Delhi grapples with recurring pollution crises, the recent fluctuations in AQI underscore the urgency of coordinated action across the region, including neighboring NCR districts, to address the multifaceted sources of air pollution that affect millions of residents every year.