Heat wave conditions continued unabated in Delhi even as the MeT department on Friday issued a "red-colour" warning for the national capital.
It also predicted that the maximum temperature may hit the 45-degree Celsius mark by late afternoon.
The IMD has four colour-coded messages -- green, yellow, amber and red. Green indicates normal conditions while red denotes extreme weather situations.
A red-code warning has been issued for the national capital, the website of the India Meteorological Department said.
On Thursday, the MeT department recorded a high of 46.8 degree Celsius, the highest in five years.
The Safdarjung Observatory had recorded a maximum of 44.7 degrees Celsius, the highest for the season so far. The minimum temperature had settled at 26.8 degrees Celsius.
In large areas, heat wave is declared when the maximum temperature is 45 degrees Celsius for two consecutive days and severe heat wave is when the mercury touches the 47-degree mark for two days on the trot.
In small areas, like the national capital, heat wave is declared if the temperature soars to 45 degrees Celsius even for a day, India Meteorological Department's regional weather forecasting chief Kuldeep Srivastav said.