"It was the hottest July 10 in the past two years," said an official of the India Meteorological Department (IMD).
The Delhi government said the peak demand for electricity was successfully met.
"The maximum demand today (Thursday) was 5,789 MW at 4.11 pm. This is the highest demand Delhi has ever met," a Delhi government official said.
The Met Office has forecast a cloudy on Friday.
"The skies will be clear in the morning but will turn partly cloudy noon onwards," he added.
Thursday's minimum temperature settled at 30 degrees Celsius, three notches above the season's average.
Friday's maximum and minimum temperatures are likely to hover around 41 degrees and 30 degrees Celsius, according to weather official.