Delhi is heating up at an alarming pace, with mean Land Surface Temperature (LST) across the Capital rising by nearly 3 degrees Celsius (°C) in March over an 11-year period between 2015 and 2016, according to a new satellite-based analysis released on Monday.
The study, conducted by think-tank Envirocatalysts, examined data across 247 wards in Delhi, and found that the mean LST in the Capital increased from 29.1°C in March 2015 to 32.0°C in March 2026 – a rise of 2.9°C.
LST, measured using thermal sensors on satellites, is the radiative temperature of the land surface (soil or canopy), usually measured using thermal infrared or microwave sensors. It differs from air temperature, which is recorded over the surface.
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The analysis revealed stark variations within the city. South Delhi’s Sangam Vihar A ward suffered the most, recording a mean LST increase of 6.1°C between 2015 and 2026. It was followed by Meethapur and Sangam Vihar-B (5.2°C each), Madangir (5°C), and Tigri (4.9°C).
Experts stressed that these locations – mostly dense urban settlements – indicated that the impact of concretisation and rapid growth has created a heat stress over the past decade.
Which were the hottest areas in Delhi in March?
In March 2026, the hottest wards were Mahipalpur (34.4°C) and Harkesh Nagar (34°C), while the coolest was Nangal Thakran at 29.2°C.
“A five degrees difference within the same city, in the same month, under the same official weather alert,” noted the analysis, which also looked at India Meteorological Department (IMD) for Safdarjung, which showed Delhi’s mean March maximum has shifted from 30.0°C in 2011 to 32.6°C in 2026, a rise of 2.6 °C over 15 years.
At the other end of the spectrum, northwest Delhi’s Prem Nagar, southwest Delhi’s Isapur and northwest Delhi’s Mubarakpur wards showed the least increase in LST over this period – 0.6°C. They were followed Najafgarh (0.9°C) and Rohini-F and Bhajanpura (1.0°C each).
“The important point of this analysis is that it shows which locations in Delhi need localised heat adaptation plans and granular policy changes,” said Sunil Dahiya, founder of Envirocatalyst. “Areas that once had parks, water bodies or small vegetation cover were replaced by constructed surfaces. That directly contributes to the rise in surface temperature.”
Data from the India Meteorological Department (IMD) at Safdarjung corroborated the trend, showing Delhi’s mean March maximum temperature rose from 30.0°C in 2011 to 32.6°C in 2026 – an increase of 2.6°C over 15 years.
The study further looked at Universal Thermal Climate Index (UTCI) as well. UTCI is defined as the equivalent air temperature at which a reference person experiences physiological strain. It integrates all four environmental drivers of heat exchange: air temperature, radiant temperature, humidity, and wind. “In May and June, every single one of Delhi’s 247 wards was in the Strong Heat Stress zone with a Universal Thermal Climate Index (UTCI) above 32°C every year from 2015 to 2025, without a single break,” said the analysis, stating in May, surface temperatures in individual wards touched 52°C.
This includes Anand Vihar, Badarpur, Chhawala, Dilshad Colony, Dilshad Garden, Gharoli, Hari Nagar Extension, Harkesh Nagar, IP Extension, Isapur, Jhilmil, Kalyanpuri, Pul Pehladpur, Meethapur, Sarita Vihar and Tughlakabad.
Data also showed that the highest average LST in May was recorded at Isapur at 50.7°C. In contrast, the city’s average LST in May was 44.1°C.
In April, Delhi’s mean LST rose by 3.5°C between 2015 and 2025. The Bhati ward in south Delhi recorded the highest April increase at 6.1°C, followed by Madanpur Khadar East and Badarpur at 5.9°C each. In June, delayed monsoons pushed the city mean close to or above 47°C in years such as 2019 (47.62°C) and 2024 (46.91°C).
“While we discuss other urban challenges, we cannot afford to miss the compounding threat of heat stress… This ward-level data can be used by the government and policymakers to make real-time, localised decisions,” Dahiya said.