The thermometer hit 50.6 degrees Celsius (123 Fahrenheit) in the Rajasthan desert city of Churu on Saturday, the weather department said.
All of Rajasthan suffered in severe heat with several cities hitting maximum temperatures above 47 Celsius.
In May 2016, Phalodi in Rajasthan recorded India's highest-ever temperature of 51 Celsius (123.8 Fahrenheit).
The Indian Meteorological Department said severe heat could stay for up to a week across Rajasthan, Maharashtra, Madhya Pradesh, Punjab, Haryana and Uttar Pradesh states.
Several deaths from heatstroke have already been recorded.