Large power cuts have crippled the city of Cairo, bringing transportation services to a halt and delaying the start of the stock exchange.
The country has been beleaguered by frequent blackouts since summer began -- some of them lasting for several hours.
The government has apologized, blaming the cuts on a spike in energy consumption during the warmer months.
The outages - coupled with soaring temperatures - have created challenges for Muslims in the midst of Ramadan, a dawn-til-dusk fast that began on July 20th.
Many of the city's 18 million residents were left in the dark Thursday, as temperatures hovered near 40°C.
Friday's high is expected to reach 41°C.
With files from the Associated Press