North India Faces Record-Breaking Temperatures
- Rising Electricity Demand and Power Failures Amid Heatwave
- Climate Change Intensifying Heat Extremes Across India
- Why Night-Time Temperatures Are Becoming More Dangerous
- Urban Heat Islands and Rising Humidity Worsen the Crisis
- Impact on Health, Economy, and Vulnerable Communities
- Scientists Warn of a Long-Term Climate Emergency
A severe heat wave across North India and Pakistan has pushed temperatures to record highs, exposing millions to dangerous heat stress. Experts warn that climate change, rising humidity, urbanisation, and hotter nights are turning Indian summers into a major public health and economic crisis.
Heat wave in North India and Pakistan
By Justice Markandey Katju
A severe heat wave is sweeping over North India and Pakistan.
Delhi, where I live, recorded its warmest May day since 2002, with temperatures hitting 46 °C (114.8 °F) on Tuesday, May 26, 2020. During the same day, North India became the world's hottest region as Rajasthan hit a scorching 50 °C (122 °F).
To get some relief from the baking heat, some people use air conditioners, while most people ( who cannot afford them ) use fans. But for that, electric power is required.
India's peak power demand surged to a new all-time high of 265.44 GW on Wednesday, marking the third consecutive day of record-breaking electricity usage as a blistering heatwave grips large parts of the country, driving up air-conditioner and cooler consumption. The fresh record was achieved at 3:45 pm (1545 hours), according to the Ministry of Power. It surpassed Tuesday’s previous high of 260.45 GW, which itself had eclipsed Monday’s record of 257.37 GW.
Sometimes the electricity fails due to the heavy load, which causes fuses to blow up, and then life becomes hellish.
India's ( and perhaps Pakistan's too ) present heat wave is more brutal and lethal than ever before. Across north, central and peninsular India, heat waves are arriving earlier, lasting longer, and stretching deep into the night, exposing millions to dangerous levels of heat stress.
India’s summers are no longer just getting hotter; they are becoming more relentless, more humid and increasingly difficult to escape. Across north, central and peninsular India, heat waves are arriving earlier, lasting longer, and stretching deep into the night, exposing millions to dangerous levels of heat stress. For instance, Meenambakkam weather station in Chennai had recorded a maximum temperature of 41°C at 5.30 pm earlier this week, which is unheard of for a coastal city where sea breeze neutralises the afternoon heat.
The severity of the late April heatwave, which has now continued deep into May, has once again highlighted how climate change is amplifying extreme weather across the country. According to a new analysis by ClimaMeter, human-induced climate change intensified India’s deadly April heat wave, pushing temperatures in major cities such as Delhi, Ahmedabad and Lucknow to nearly 45°C, while Banda in Uttar Pradesh touched 47.6°C. The study found that events like the April 2026 heat wave are now occurring in an environment that is up to 2°C warmer than in previous decades. Nearly 44 million people and about $341 billion worth of economic activity were exposed to the most extreme heat conditions.
Scientists say the crisis is no longer driven by temperature alone. A combination of climate change, rising humidity, hotter nights, urbanisation and dry soil conditions is now intensifying the heat burden across India.
India’s Core Heatwave Zone (CHZ), covering Rajasthan, Delhi, Uttar Pradesh, Madhya Pradesh, Bihar, Odisha, Telangana and parts of Maharashtra, is witnessing a statistically significant increase in both the frequency and duration of heat waves.
According to India Meteorological Department (IMD) data, heat wave frequency in the CHZ has increased by 0.1 days per decade since 1961, while the total duration of heat waves has risen by 0.44 days per decade. Severe heat waves have also become more frequent and prolonged.
Meteorologists say the ongoing heat wave conditions are being driven by persistent hot northwesterly winds flowing from the desert regions of Rajasthan and adjoining Pakistan into northern and central India.
“In the absence of any weather system over the Indian mainland, hot northwesterly winds from the desert of the adjoining Sindh region of Pakistan and Rajasthan are penetrating deep into the country,” said Mahesh Palawat, vice president-meteorology and Climate Change at Skymet Weather. He said the uninterrupted flow of these winds over several days has triggered severe heat wave conditions across large parts of India.
But what is making recent heat waves especially dangerous is the rise in nighttime temperatures.
Several parts of the country are recording minimum temperatures close to 30°C, leaving little relief even after sunset. According to WHO Housing and Health Guidelines, indoor temperatures should ideally not consistently exceed 24°C because of the risk of cardiovascular strain and sleep disruption.
IMD data shows that India’s average night-time temperatures are rising by around 0.21°C per decade. Among the warmest years for night temperatures were 2010, 2024, 2016 and 2022. The warming trend is visible across almost the entire country. Data from the Council on Energy, Environment and Water (CEEW) shows that 35 out of 36 states and Union Territories are witnessing rising night-time temperatures, with Sikkim, West Bengal, Andhra Pradesh, Karnataka and Bihar showing particularly strong increases.
Scientists warn that hotter nights dramatically increase health risks because the human body gets less time to recover from daytime heat exposure.
“The late April 2026 heat wave in India puts a spotlight on an evolving pattern of earlier, longer, and more intense hot extremes in the region in a changing climate,” said Neven Fuckar from the University of Oxford. “High daytime air temperatures combined with warm nights reduce physiological recovery and increase cumulative heat stress.”
The impact is especially severe on outdoor workers, the urban poor, elderly people and schoolgoing children who lack access to cooled spaces.
Even in places where temperatures are not breaking records, high moisture levels are making conditions feel far worse by limiting the body’s ability to cool itself through sweating. According to the analysis, India’s average relative humidity increased from 67.1% during 2015-2019 to 71.2% during 2020-2024.
The increase has been especially sharp in Delhi, Haryana, Telangana, Uttar Pradesh, Maharashtra and Rajasthan.
“This event shows that extreme heat is becoming a growing socio-economic risk across India,” said Haosu Tang of the University of Sheffield. “Severe pre-monsoon heat can reduce labour productivity, increase electricity demand, and place additional stress on water resources before the monsoon arrives.”
India’s rapidly expanding cities are also worsening the heat burden through the urban heat island effect. Dense concrete structures, asphalt roads, low tree cover and trapped waste heat are causing cities to remain significantly warmer than surrounding rural areas, particularly at night.
According to studies cited in the report, urban heat island intensity in Indian cities can vary between 2°C and 10°C.
Climate scientists also point to dry soils and reduced winter snowfall as important contributors to worsening heat extremes. Reduced snowfall in the Himalayas lowers surface reflectivity, allowing more solar heat to be absorbed. Dry soils meanwhile, reduce evaporative cooling, allowing more solar energy to directly heat the air.
Raghu Murtugudde, emeritus professor at the University of Maryland and visiting professor at IIT Kanpur, said high-altitude regions such as Uttarakhand are warming faster because thinning snow cover and black carbon pollution are accelerating warming through what scientists call the ice-albedo feedback.
The impacts are already being felt across sectors. Lucknow reported a 30-40% increase in heat-related illnesses during the April heatwave, while electricity demand surged to record levels. Economists warn that prolonged heat combined with erratic monsoon patterns could push inflation above 5% and drive up food prices.
(Justice Katju is a retired Judge of the Supreme Court of India and a former Chairman of the Press Council of India. These are his personal views.)
