The peak of the heat wave is expected Thursday and Friday, the National Weather Service said. While it’s brought warmer temperatures than in recent weeks, it is not particularly extreme in terms of all-time Southern California highs. “This is definitely more normal heat for this time of year,” Sam Zuber, an NWS meteorologist said.

Southern California Edison says high heat is not the only factor it monitors. The utility also tracks dry vegetation and humidity levels at its emergency operations center in Irwindale to determine if a public safety power shutoff is necessary to prevent wildfires.