Mexico was hit by hours of rolling blackouts late Tuesday due to high temperatures and temporary drops in electrical power generation.

The government’s National Center for Energy Control said the blackouts lasted a total of about five hours, though it was likely less for individual customers because it was a rolling blackout distributed around the country.

The center said the largest power cut affected about 5% of customers, and lasted about four hours.

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The larger blackout was partly caused by a spike in power demand in the early evening, when many Mexicans arrive home and turn on television sets, fans and air conditioners.

Mexico has broken several high temperature records this year, with about a third of the country expected to reach 113 degrees Fahrenheit on Wednesday. Greater Mexico City, where about one-sixth of the population lives, reached a high of 92 degrees on Tuesday.

Mexico City is located in a high mountain valley and usually cools down at night, but that has not been happening as much this year.

Power generation also dropped unexpectedly due to other reasons including lower output from hydroelectric dams, which have been affected by drought, and clouds affecting solar power.

The blackouts were an embarrassment for President Andrés Manuel López Obrador, who has made a priority of increasing the role of the state-owned power company, known as the CFE, and reducing opportunities for private power generators.

Many of the state-owned plants that López Obrador has given priority to are dirtier because they burn fuel produced at government-owned refineries. The president has sought to limit cleaner, private power generation using natural gas or renewables.