Of the 15 hottest places in the world in the past 24 hours, eleven were in India with the others in neighbouring Pakistan, weather monitoring website El Dorado reported on Monday.
Churu in Rajasthan recorded the highest temperature of 48.9 degrees Celsius on Monday, according to the Indian Meteorological Department. El Dorado put the temperature at 50.3 degrees.
Churu has issued a heat wave advisory and government hospitals have prepared emergency wards with extra air conditioners, coolers and medicines, said Ramratan Sonkariya, additional district magistrate for Churu.
Water is also being poured on the roads of Churu, known as the gateway to the Thar Desert, to keep the temperature down and prevent them from melting, Sonkariya added.
A farmer from Rajasthan's Sikar died on Sunday due to heatstroke, state government officials said.
The temperature in Delhi touched 44.6 degrees Celsius on Sunday. Food delivery app, Zomato, asked its customers to greet delivery staff with a glass of cold water.
Heat wave warnings were issued on Monday for some places in western Rajasthan and Madhya Pradesh.
The monsoon, which brings down the heat, is likely to begin on the southern coast on June 6, the weather office said last month.
The three-month, pre-monsoon season, which ended on May 31, was the second driest in the last 65 years, private forecaster Skymet, said, with a national average of 99 mm of rain against the normal average of 131.5 mm for the season.