SACRAMENTO, Calif. (KTXL) — A Flex Alert was issued by the California Independent System’s Operator (ISO) on Wednesday from 4 p.m. to 9 p.m. due to extreme heat throughout the region.

According to CAL ISO, high temperatures are expected in much of California, which could lead to added stress on energy supplies. 

The FOX40 Weather Center said the high for Wednesday is forecasted to be 101 degrees. 

Consumers are urged to conserve electricity and are advised to use major appliances such as washers, dryers and dishwashers before 4 p.m. CAL ISO also recommends pre-cooling homes to 72 degrees.

Flex alerts are typically issued a day before its needed, so consumers can plan ahead. 

What is a Flex Alert?

A Flex Alert is a call for consumers to voluntarily conserve electricity when there is an anticipated shortage of energy supply, according to 

If consumers reduce their use of electricity during a Flex Alert, “it can prevent more dire emergency measures,” including rotating power outages, according to the website. 

Typically, a Flex Alert is issued in the summer when temperatures get extremely hot, which drives up electricity use. When electricity use increases, it could make the available power supply scarce, especially in the evening hours when temperatures are high in the evening hours and people return home and switch on their air conditioners, lights, and appliances. 

According to the Flex Alert website, here are other contributing factors to the alert: 

  • Unplanned power plant outages 
  • Fires that threaten or affect transmission or affect transmission lines
  • Humid, hot weather and heat storms

What consumers should do when a Flex Alert is issued

According to the Flex Alert website, consumers should shift their energy use to the morning and early afternoon hours. 

In the morning before a Flex Alert, consumers should pre-cool their homes to 72 degrees, close blinds and drapes to keep the sun from heating up the home, turn off all necessary lights, and use major appliances. 

It’s also recommended to set your pool pumps to run early in the morning, and charge your phones, laptops, and electric vehicles. 

What consumers should do during a Flex Alert

During the hours of a Flex Alert and when conservation is needed, it’s recommended to set your thermostat to 78 if health permits. 

People should avoid using appliances such as dishwashers, dryers and ovens along with turning off unnecessary lights. 

Electrical devices that aren’t being used should be turned off, blinds and drapes should continue to be closed, and use fans when possible.