Managers of California's power grid are asking for voluntary electricity conservation as forecasters predict more extreme heat statewide.
The California Independent System Operator predicts demand on the system will set a new all-time record Friday, and Angelenos are not loving it.
Consumers are asked to cut back on use of electricity between 1 p.m. and 10 p.m. when use of air conditioners is at its peak.
The National Weather Service warns that the heat will bring a high risk of heat-related illness, especially for the elderly, the infirm and children.
Forecasters also say the heat will be dangerous to anyone without proper hydration or adequate cooling.
In Southern California, it's expected to be between 100 and 114 in the valleys and foothills. Health officials declared a heat emergency in the San Fernando, Santa Clarita and Antelope valleys and the Pomona area through Sunday.
A heat emergency has also been called for the San Gabriel Valley through Friday and in downtown L.A. through Saturday.
"This situation of an extended heat wave like we're having in LA County this week is very unusual. We haven't had this for a number of years," said L.A. County health officer Doctor Jeffrey Gunzenhauser. "And the real message is for people to reach out to their neighbors and friends and make sure they're safe and have access to air conditioning."
Officials recommend avoiding any strenuous outdoor activity if possible - and to drink plenty of water and stay indoors in air-conditioned areas.
KPCC's Nick Roman spoke with National Weather Service meteorologist Todd Hall, who said that weather from Tropical Storm Lidia to the south will bring cooling to the region over the weekend, but will also likely come with increased humidity and some showers and thunderstorms.