Firefighters coordinate efforts at a burning property while battling the Fairview Fire on Monday, Sept. 5, 2022, near Hemet, California.

Tens of millions of people were warned of the dangers of heat during the Labor Day weekend. As of Tuesday, the ongoing heat is fueling wildfires and threatening California's electrical grid, prompting officials to urge residents to reduce their power use.

According to the National Weather Service, Southern California is under an excessive heat warning for the rest of the week. Hundreds of people were forced to leave Hemet, California on Monday due to a fire caused by the hot weather. The district said in an online statement that schools are closed because of the fire and because of the high temperatures.

In other areas of Southern California, outages are expected. According to energy officials, the electrical load this afternoon could reach more than 51,000megawatt, the highest demand California has ever seen, as residents struggle to keep their homes cool.

The California Independent System Operator, which manages most of the grid, asked residents to cut back on their electricity use last week. Californians were asked to set their thermostat to 78 degrees. In the evening, to avoid further straining the state's grid. The California Independent System Operator said on Monday that it is very likely that the grid will experience rotating outages this week unless consumers can reduce their energy use more.

The city opened cooling centers in nursing homes and libraries to help people without air conditioning. Water Drop LA gives out free bottled water to people who need it.

Climate change is making heat waves more frequent. Vulnerable people like the elderly, those with illness, and people without easy access to air conditioning can all be killed by events like this. Hundreds of people died in the US and Canada due to a heat wave in the Pacific Northwest last June.