A heat wave will settle on the Southland Friday, creating “dangerously hot conditions” that will threaten human health through the Labor Day holiday and cause an increased danger of wildfires, the National Weather Service said.
“The very hot conditions through Labor Day will bring an increased threat of large fire activity including fires with large vertical growth,” the national Weather Service tweeted. “Dangerous heat” is expected, it warned on its website.
Woodland Hills is forecast to hit highs 117 degrees Sunday, according to the NWS.
The anticipated high temperatures are sparking concerns about demand on the state’s power grid as residents turn up their air conditions units.
The California Independent System Operator, which manages the power grid, announced that a Flex Alert — a call for voluntary conservation — will be in effect from 3 to 9 p.m. Saturday through Monday. Urging voluntary conservation is an effort to stave off to much strain on the state’s electrical system, possibly leading to rolling power outages, like those that occurred during high heat last month.
An excessive heat warning issued by the NWS will be in effect from 10 a.m. Friday until 8 p.m. Monday in the San Gabriel and Santa Monica mountains, Santa Catalina Island and the San Fernando, Santa Clarita, San Gabriel and Antelope valleys. In Orange County, the warning will be in force in coastal areas from 10 a.m. Saturday until 8 p.m. Monday.
“Extreme heat will significantly increase the potential for heat related illnesses, particularly for those working or participating in outdoor activities.” according to an NWS statement.
“Drink plenty of fluids, stay in an air-conditioned room, stay out of the sun, and check up on relatives and neighbors,” the NWS advised, adding that children, seniors and pets must never be left unattended in vehicles under any circumstances since temperatures can quickly turn lethal in the current conditions.
“Take extra precautions if you work or spend time outside. 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 weather service also noted that the Occupational Safety and Health Administration recommends scheduling frequent rest breaks in shaded or air conditioned environments.
The high heat is being attributed to high pressure, which is forecast to settle into the Great Basin area through the weekend.
In forecasting an increased fire danger, forecasters said they were mainly focusing on the dryness that will take hold in the region, partly because of the absence of monsoonal moisture. Forecasters said humidity levels will fall to single digits in interior areas of L.A. County. But no red flag warnings indicating a high risk of wildfires are likely to be issued, principally because a key component of fire weather is missing — strong winds.
Cooling centers are open Friday and through the weekend in the cities of Los Angeles and Long Beach and in L.A. and Orange counties. Authorities noted that due to the coronavirus pandemic, cooling centers will be limited in capacity and restrictions will be in place, such as requiring face coverings.
Sunny skies were forecast for all of L.A. County Friday, along with highs of 80 at LAX; 85 in Avalon; 89 in Downtown L.A.; 90 in Long Beach; 93 on Mount Wilson; 97 in San Gabriel; 100 in Pasadena and Burbank; 103 in Saugus; 104 in Woodland Hills; 107 in Palmdale; and 108 in Lancaster. Temperatures will be several degrees higher Saturday, including a high of 107 degrees in Downtown L.A., which relatively seldom reaches triple-digit territory. Pasadena will be at 113 and Woodland hills at 116. A significant cooling trend will begin Monday.
Sunny skies were expected in Orange County, along with highs of 77 in Newport Beach and San Clemente; 78 in Laguna Beach; 89 on Santiago Peak; 91 in Irvine; 92 at Fremont Canyon; 93 on Ortega Highway at 2,600 feet and in Fullerton and Yorba Linda; 94 in Anaheim and Mission Viejo; and 96 at Trabuco Canyon. Temperatures will rise sharply Saturday, reaching 115 in Anaheim and Fullerton, with a correspondingly sharp decrease Monday.