Several pockets of the national capital also witnessed record temperatures.
Gurgaon, Delhi's neighbour, turned into a hot cauldron on Sunday, with mercury touching an unbearable high of 48.1 degree Celsius amid a punishing heatwave in the country's northern region. Unfortunately, little to no relief is expected in the coming days as the weather office, earlier in the day, issued a warning of a severe heatwave for northwest India, including a Red alert for Rajasthan.
"We have issued Red Alert for Rajasthan for an intense spell of the heatwave, and a Yellow alert for tomorrow. Similarly, we have issued an Orange alert for Punjab, Haryana, Uttar Pradesh, eastern Madhya Pradesh and Delhi," said a senior scientist at the Indian Meteorological Department or IMD, Naresh Kumar.
Several pockets of the national capital also witnessed record temperatures with 49.2 degrees at Mungeshpur and 49.1 at Najafgarh.
Recently, NASA shared an image which showed "heat islands" in Delhi at night. The image, taken shortly before local midnight on May 5, showed urban areas and agricultural lands northwest of Delhi.
Cities are usually markedly warmer than the surrounding countryside due to human activities and the materials used in the built environment. The image clearly delineates these urban “heat islands.”
Nighttime temperatures in Delhi and several smaller villages were above 95 degrees Fahrenheit (35 degrees Celsius), peaking at about 102 degrees F (39 degrees C), while the rural fields nearby had cooled to around 60 degrees F (15 degrees C). The data suggests that city dwellers are experiencing considerably higher temperatures than the average temperatures reported for their regions.
"Talking in general, most parts of Northwest India, including Punjab, Haryana, Rajasthan, Madhya Pradesh and Uttar Pradesh have experienced heatwave to severe heatwave conditions yesterday. Vidarbha also experienced the heatwave conditions," said Mr Kumar.
The IMD uses four colour codes -- green (no action needed), yellow (watch and stay updated), orange (be prepared) and red (take action)-- for weather warning.
It said the heatwave could lead to "moderate" health concerns for vulnerable people -- infants, elderly, people with chronic diseases -- in affected areas. "Hence people of these regions should avoid heat exposure, wear lightweight, light-coloured, loose, cotton clothes and cover the head by use of cloth, hat or umbrella etc," the Met office said.
For the plains, a 'heatwave' is declared when the maximum temperature is over 40 degrees Celsius and at least 4.5 notches above normal.
The country suffered its hottest March in more than 100 years and April saw many places, including Delhi, recording unusually high temperatures in excess of 40 degrees Celsius on most days.