Thousands of Southern California residents were without power Monday night as dangerously hot weather prompted an all-time high for electricity demand.

More than 6,000 Los Angeles Department of Water and Power customers were without power in the service area Monday night, according to spokeswoman Mary Anne Pierson. Roughly 2,000 customers in the Valley Glen area were impacted, she added.

Southern California Edison had also reported some outages in a number of its service area, including Beverly Hills, Pacific Palisades, Inglewood and Chino Hills.

Most of the power outages were caused by the sweltering heat combined with high electricity usage.

By 11 p.m., some service was already back on. LADWP and SCE crews were continuing to work on restoring electricity to all other affected residents, but it was not immediately clear how long the outages would last.

Earlier in the day, LADWP had advised customers to conserve energy in an effort to reduce the strain on the power grid and minimize the risk of potential power outages.

“This afternoon, we do expect to hit a record, all-time energy use in the city of Los Angeles, demand from our customers. And it’s really just air conditioners that are running continuously,” said Joe Ramallo with LADWP.

To reduce the stress on the grid, residents have been advised to adjust air conditioning thermostats to 78 degrees between 11 a.m. through 8 p.m., typically the hottest hours of the day, according to an LADWP news release.

Customers were also urged to limit use of major appliances — such as washing machines, dishwashers and vacuum cleaners — during daytime hours.

They were also being encouraged to visit “cooling centers” to beat the heat.

City facilities, such as senior citizen centers, recreation and parks facilities and libraries, may be used as cooling centers, the L.A. Emergency Management Department has suggested. Business hours varied and can be found online.

Temperatures between 100 and 110 degrees were forecast in many areas from late morning through the evening, with even the beaches — typically viewed as a hot-weather escape — facing temperatures of 90 to 100 degrees.

An excessive heat warning was issued through 7 p.m. Tuesday by the weather service for much of Los Angeles, Orange, Riverside, San Bernardino and Ventura counties.

Temperatures were set to decrease beginning Wednesday, but humidity was expected to increase due to precipitation caused by Odile.

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