Tokyo marked a record ninth consecutive “extremely hot day" above 35 degrees Celsius on Sunday, the Meteorological Agency announced, after the capital saw the mercury hit 35.3 C just after 12 p.m.
The agency said the streak bested the previous record set from July 31 to Aug. 7, 2015.
The news comes after the central government on Friday requested that households and businesses enter a three-month period of conserving electricity to prevent a power crunch amid the record-breaking heat wave.
The request was the first of its kind by the government in seven years.
The unusually hot weather in recent days — including temperatures around 40 C in some areas — has kept power demand extremely high, with supply expected to remain tight throughout the summer due to persistent heat and infrastructure issues.
While a numerical target has not been set for the period through September, the government is calling for people to reduce energy consumption without disrupting daily life and economic activities.
Due to the heightened risk of heatstroke, the Ministry of Economy, Trade and Industry is calling on people to continue to use air conditioners and instead save electricity through measures such as turning off unnecessary lights.
A government spokesman also urged people to remove masks outdoors to prevent heatstroke as many in the country have continued wearing them since the outbreak of the coronavirus pandemic.
Energy-saving measures are especially encouraged between 5 p.m. to 8 p.m., when solar power generation declines.