'Flex Alert' issued for energy conservation due to California heat

Operators of California's power grid called for electricity conservation Wednesday as summer heat set in throughout much of the state, including scorching temperatures under a dome of high pressure over the Mojave Desert.

The California Independent System Operator asked consumers to use less power especially during the peak demand period between 2 p.m. and 9 p.m.

Electricity supplies were expected to be tight due to increased use of air conditioners, power plant outages and reductions in transmission line import capacity due to high temperatures in neighboring states, the CAISO said.

Flex Alerts are a voluntary level of conservation. People are urged to set air-conditioner thermostats at 78 degrees or higher, cool with fans, close drapes, turn off unneeded lights and only use major appliances in the morning before heat builds or late evening after peak demand.

The only previous Flex Alert this year was on June 20.

The National Weather Service issued an excessive-heat warning for a vast swath of California's southeastern flank from below the Eastern Sierra through the Mojave Desert to the Mexican border.

Heat advisories were posted in adjacent regions including the Coachella Valley and the Anza Borrego desert.

The town of Needles on Interstate 40 at the Colorado River baked at 115 degrees at 1 p.m. Death Valley was expected to be near 125 degrees by Thursday, the NWS said.

The Central Valley sizzled in triple digits from Redding to Bakersfield.