Unpredictable Monsoon Weather & High Heat Grips The Southland

(FOX 11 / CNS) With a heat wave gripping the Southland and power demand on the rise, the manager of the state's energy grid issued a "flex alert," urging residents to conserve electricity between 2 and 9 p.m. today -- a warm, muggy day when showers and thunderstorms are possible -- to reduce strain on the system.

RELATED: 'Flex Alert' Issued For California, 'Heat Alert' For Antelope Valley

RELATED: Drought Watch: Staying Cool in the Excessive Heat

The alert went into effect Tuesday and was to remain in force today, according to the California Independent System Operator. The National Weather Service, meanwhile, warned of a chance of thunderstorm today and again tonight in the Greater Los Angeles area, where temperatures will range from the 70s at the beach to about 100 in the Antelope Valley.

"Consumers are urged to reduce their energy use during the late afternoon when air conditioners drive consumption to the highest point of the day," according to the alert.

According to Cal-ISO, a flex alert is issued when the state's power grid is under stress due to elevated demand or transmission system outages. The alerts call for voluntary conservation so the state will not have to dip into energy reserves. The agency offered a series of tips for onserving energy:

The heat also raised health concerns, and the Los Angeles County Department of Public Health declared a heat alert in the Antelope Valley for
Tuesday and today. According to the National Weather Services, temperatures are expected to range from about 95 to 105 in the Antelope Valley.
Temperatures will likely hover in the same range -- although down by a couple of degrees -- into the weekend, meaning the heat alert could be

County health officials urged residents to take precautions, particularly in the case of older adults, infants and people who take part in outdoor activities or are sensitive to the heat.

Schools, day camps and sports organizations were also advised to take precautions, limiting outdoor activities to early or late in the day.
Health officials issued a series of safety tips, including:

People with limited access to air-conditioning can also take advantage of county cooling centers. A list of centers is available online at: http://bit.ly/BeatTheHeat2015 or via the county's information phone line at 211.

The National Weather Service forecast cloudy skies today and highs of 73 in San Clemente; 74 in Newport Beach; 75 in Avalon, Laguna Beach and at LAX; 82 in Mission Viejo; 83 in Long Beach; 85 in downtown L.A., Irvine and Anaheim; 88 in Fullerton and on Mt. Wilson; 89 in Yorba Linda; 90 in San Gabriel and Burbank; 94 in Pasadena; 95 in Woodland Hills and Saugus; 97 in Palmdale; and 98 in Lancaster. Thursday's temperatures will be a little lower -- 5 degrees in many communities.

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