While the national capital's Mungeshpur station recorded a temperature of 49.2 degrees, Najafgarh recorded 49.1 degree Celsius.
The weather agency advised people in northern India to avoid venturing outside their homes unless absolutely essential and to drink plenty of water even if not thirsty.
Weather station at Safdarjung observed a max temperature of 45.6 degrees Celsius while the west part of Delhi reported temperatures ranging between 46 to 48 degrees Celsius.
On May 29, 1944, Safdarjung recorded a max temperature of 47.2 degrees Celsius.
Maximum temperatures reached 47.5 degrees Celsius at Jafarpur, 47.3 degrees Celsius at Pitampura and 47.2 degrees Celsius at Ridge.
Other parts of Delhi observed maximum temperatures rise to 46.8 degrees Celsius at Ayanagar, 46.4 degrees Celsius at Palam and 45.8 degrees Celsius at Lodhi Road, the weather agency said.
In Haryana, Gurgaon recorded the highest temperature today amongst other stations which are 48.1 degrees Celsius and Mukhtsar in Punjab reported 47.4 degrees Celsius.
An 'orange' alert has been issued to caution people about a severe heatwave on Sunday.