The Indian capital, Delhi, saw temperatures rise to 47.6C on Tuesday, as most of north India faced severe heatwave conditions.
The heatwave, which officials say is likely to last until the weekend, comes even as the region struggles with rising Covid-19 infections and swarms of locusts that are ravaging crops.
Churu in Rajasthan state recorded a temperature of 50C - India's highest.
Officials have warned people to stay indoors as far as possible.
The temperatures are the highest that the country has seen in decades for this time of the year. In fact, global weather tracking website El Dorado said the region was the hottest in the world on Tuesday.
Weather officials told local media that part of the reason for the heatwave was the powerful storm - Cyclone Amphan - that struck parts of eastern India and Bangladesh last week.
"Super cyclone Amphan sucked out all the moisture from other parts of the country," Kuldeep Shrivastava, the head of the regional weather forecasting centre told the Hindustan Times newspaper.
Heat waves in recent years have caused a number of deaths across India. There is still no data about the impact of the current temperatures on people.
However, they come even as thousands of migrants are walking on the highways after fleeing cities to try and go back to their villages. Many are walking with little food and water, and will be among the most exposed to the weather.
Previously, those who have died have included people like daily-wage labourers, rickshaw operators and vegetable vendors - those most exposed to the sun.
In addition to that, the heatwave has affected efforts to combat swarms of locusts that are destroying crops in parts of the country, including Rajasthan.
More than 100 workers are battling the insects, using vehicle-mounted sprayers, pesticides and drones in the searing heat.