The Southland continued to suffer from the worst heat wave in years Sunday, with temperatures set to rise again to dangerous levels beginning Tuesday.
Excessive heat warnings remained in effect through 9 p.m. Wednesday in the Antelope, Santa Clarita and San Fernando valleys, where more triple-digit temperatures were expected Sunday. A high of 108 was expected in Lancaster, 104 in Palmdale, and 100 in Woodland Hills and Santa Clarita.
“Extreme heat will significantly increase the potential for heat related illnesses, particularly for those working or participating in outdoor activities,” warned a National Weather Service statement.
“Take extra precautions if you work or spend time outside,” it urged. “When possible, reschedule strenuous activities to early morning or evening. Know the signs and symptoms of heat exhaustion and heat stroke. Wear lightweight and loose-fitting clothing when possible.”
Managers of California’s power grid issued a statewide Flex Alert on Sunday, calling for voluntary electricity conservation through Wednesday and warning of rolling blackouts amid record-breaking heat.
The Flex Alerts are in effect from 3 p.m. to 10 p.m. each day.
The California Independent System Operator urged consumers to help by shifting energy use to morning and nighttime hours and conserving as much energy as possible during the late afternoon and evening hours.
CAL-ISO initiated some rolling blackouts Friday and Saturday for the first time since 2001, with most lasting no more than 20 minutes.
The high in downtown Los Angeles was 88 degrees Sunday — an improvement from Saturday’s high of 99 — but that number was expected to jump to 93 on Monday and 98 on Tuesday.
Cooling centers opened in the city and county of Los Angeles to give residents a place to escape the heat. Due to COVID-19 social distancing requirements, capacity is limited and people are should call ahead to check space availability, according to the Los Angeles Department of Recreation and Parks. Information on the county’s cooling centers as well as heat-related illnesses and prevention is at publichealth.lacounty.gov.
The heat was making life tough for firefighters battling two wildfires in Los Angeles County. The Lake Fire in the Lake Hughes area had burned 17,862 acres and was 12% contained Saturday afternoon, while the Ranch 2 Fire in Azusa had burned 2,256 acres and was 7% contained.
The NWS warned of elevated critical fire-weather through Monday, in part because of very dry vegetation, providing fuel for wildfires. Another factor is the fact that surface winds coming from the north will be weak, keeping the ground warm. But no red flag warnings have been issued.
Unhealthy air quality was expected Sunday in the San Gabriel Valley and the San Gabriel Mountains, the Santa Clarita Valley, the west San Fernando Valley and the Pomona-Walnut Valley.
A flash flood watch was in effect through Sunday evening for the Antelope Valley and the L.A. County mountains excluding the Santa Monica range.
Tuesday was expected to be the worst day of the entire heat wave, with highs expected to reach 109 in Lancaster and Santa Clarita, 107 in Chatsworth and 103 in Pasadena. More dangerously high temps are forecast for Wednesday and Thursday, before the heat wave is finally expected to ease up on Friday.