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Heat prompts Flex Alert for San Diego County, rest of California on Thursday and Friday

Posted at 4:25 PM, Jun 16, 2021
and last updated 2021-06-19 09:40:33-04

SAN DIEGO (KGTV) — San Diego County, and the rest of the state, will be asked to voluntarily conserve power on Thursday during a statewide Flex Alert amid rising temperatures this week.

The California Independent System Operator, which manages the state's power grid, said that the alert would last from 5 p.m. to 10 p.m. The agency extended the alert to Friday from 6 p.m. to 9 p.m.

Residents will be asked to decrease their power usage to help relieve stress on California's power grid. The power grid operator said this time is the most critical because it's when solar production ramps down and electricity demand remains high, especially during extreme heat.

Thursday, Cal-ISO said it's "not anticipating rotating power outages."


"For the next several days, much of California and the Southwest are expected to see triple-digit heat with above normal temperatures spread more broadly across much of the Western United States. And like California, other Western states – including Arizona and New Mexico – are experiencing similar stressful grid conditions due to the extreme heat," Cal-ISO said in a release. "Under such conditions, evening is the most difficult time of day for grid operations, especially in persistent hot weather when evening temperatures stay warm, because demand for electricity remains high as solar energy diminishes."

The move is a reverse from an earlier announcement on Wednesday in which Cal-ISO said they forecast having "enough reserves to cover demand for tomorrow evening."

To conserve power during a Flex Alert, residents are asked to:

  • Set thermostats to 78 or higher, if health permits;
  • Avoid using major appliances; and
  • Turn off unnecessary lights;

During the day, residents can pre-cool their homes, use major appliances, and charge electronics to avoid power use later in the day.

A heatwave sweeping over the region has brought record temps to some parts of the county throughout the week.