Rain, Thunderstorms Lash Delhi-NCR as Air Quality Stays 'Poor' at AQI 227

Moderate rain swept across Delhi and the National Capital Region on Thursday, prompting the India Meteorological Department (IMD) to issue a yellow alert for the city. The weather office has forecast a generally cloudy sky with spells of rain, thunderstorms and gusty winds through the day.

The unsettled conditions are expected to continue on Friday, with the IMD also flagging the possibility of isolated hailstorms over Delhi, Haryana and Chandigarh until October 30. Light to moderate rainfall is likely at several places, accompanied by lightning and strong winds.

Wind speeds could touch 40-50 kmph during the morning hours, while gusts of 30-40 kmph are expected for the remainder of the day, according to the weather department. The maximum and minimum temperatures in the national capital are expected to settle at 27 degrees Celsius and 17 degrees Celsius respectively.

A yellow alert is the IMD's lowest-level warning and signals that residents should stay updated on weather developments and be prepared for possible disruption. People have been advised to exercise caution during periods of lightning, hailstorms and strong winds, and to avoid open spaces and tall trees when thunder is heard.

Meanwhile, Delhi's air quality remained in the 'poor' category on Thursday morning. The city-level Air Quality Index (AQI) stood at 227 at 8 a.m., according to the Central Pollution Control Board's (CPCB) All India AQI portal. PM2.5 and PM10 — fine particulate matter capable of penetrating deep into the lungs — were identified as the prominent pollutants.

Among individual monitoring stations, Uttam Nagar recorded an AQI of 340, placing it in the 'very poor' category. Dwarka Sector 8 followed at 308. Other stations reporting 'poor' air included CRRI Mathura Road (299), Punjabi Bagh (285), Chandni Chowk (272), Pusa (271), NSIT Dwarka (270), Sirifort (268), IGI Airport Terminal 3 (266), Nangloi (260), NSUT Jaffarpur (253), Alipur (250), Najafgarh (243), Mandir Marg (230), Burari Crossing (226) and Anand Vihar (227).

Several other locations recorded 'moderate' air quality. These included Karala (198), Ghummanhera (197), Burari (174), Vasundhara Enclave (171), Jharoda Kalan (161), Badarpur (159) and Chhawla (154).

Under the CPCB's National AQI classification, readings between 101 and 200 fall in the 'moderate' category, 201 to 300 in 'poor', and 301 to 400 in 'very poor'. Prolonged exposure to poor air can cause breathing discomfort for healthy people, while very poor air may lead to respiratory illness. Children, the elderly and those with existing heart or lung conditions are generally advised to limit outdoor exertion on such days.

Rain generally helps settle particulate matter and can improve air quality temporarily, though the effect depends on how heavy and how long the spell lasts. Delhi's air typically deteriorates from late October onwards, a period marked by cooler temperatures, calmer winds that trap pollutants near the ground, and the seasonal burning of crop residue in neighbouring states.

Residents are advised to check weather bulletins before commuting, carry rain protection during the day and follow local advisories on lightning and hailstorms. Those with respiratory conditions may wish to keep medication handy and monitor AQI readings for their locality.