LOS ANGELES - More hot weather is heading to the Southland, with the Antelope Valley and Santa Clarita Valley likely to bear the brunt of the high-pressure system.
The manager of the state's power grid has issued a Flex Alert calling for voluntary energy conservation from 4 to 9 p.m. Friday in hopes of reducing a strain on the system during anticipated high heat.
Forecasters said temperatures won't drop dramatically overnight in the area, with lows expected in the mid-70s to mid-80s.
"High pressure will continue to build over the region into the weekend, leading to warming temperatures each day mainly away from the coast," according to the NWS. "The warmest days will likely be Friday through Sunday when excessive heat will be likely for interior areas.
"Low clouds and fog will be confined to the coastal plain and possibly lower coastal valleys during the overnight and morning hours."
Forecasters said the excessive heat warning could potentially be extended to the Santa Clarita Valley on Friday and beyond, depending on how the high-pressure system unfolds. A continuing onshore flow will keep temperatures cooler along the coast.
While the weather is expected to be hot, forecasters said temperatures will likely remain just shy of daily-record levels, which are in the 110-115 range, and "certainly short of all-time records which are in the 113-117 range."
The high-pressure system is expected to weaken early next week, but it will still be warmer than usual. Triple-digit temperatures are expected throughout next week in the Antelope Valley.
As with other heat events, the NWS advised residents in the Antelope Valley to stay hydrated, avoid the sun when possible and check up on relatives and neighbors who might be susceptible to heat illness.
"Take extra precautions if you work or spend time outside," forecasters advised. "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."
The Los Angeles County Department of Public Health issued a heat alert in response to forecasted elevated temperatures. The alert will be in effect from Friday through Sunday in the western San Fernando Valley, and from Saturday through Sunday in the San Gabriel Valley and the eastern San Fernando Valley.
County officials said residents without air conditioning at home can take advantage of cooling centers, with information on locations available at https://ready.lacounty.gov/heat/ or by calling 211.