As Temperatures Soar, Another Flex Alert is Called

With temperatures expected to soar, the California Independent System Operator, which manages the state's power grid, announced another Flex Alert for Tuesday between 11 a.m. and 6 p.m.

Residents are asked to conserve power between those hours.

“The ISO thanks consumers for their tremendous conservation efforts during last Friday’s Flex Alert,” Stephanie McCorkle, ISO spokeswoman said through a news release. “Nearly 1,000 megawatts in energy reduction helped maintain grid reliability. The level of conservation is equal to the output of two large power plants.”

Temperatures in valley and mountain areas of the Southland were again expected to reach dangerous "excessive heat" levels today, fall marginally during the week and rise anew next weekend, National Weather Service forecasters said.

In Diamond Bar the high was expected to hit 96 degrees but could reach into the triple digits thanks to a hot air mass resulting from a ridge of high pressure over the southwestern United States, and high humidity levels will make it feel even hotter, according to the weather service.

"Heat index values, which take into account the air temperature and humidity, are expected to reach 105 degrees in many valley locations in Los Angeles and Ventura counties ... and to around 100 degrees in the lower mountain elevations," according to an NWS advisory.

"The combination of very hot temperatures and moderate humidity will combine to create a dangerous situation in which heat illnesses are possible," it said.

Cal-ISO did not issue a flex alert today but still urged residents to cut back on power use, particularly through 6 p.m.

Southern California Edison and the Los Angeles Department of Water and Power offered a series of tips to help customers cut back on power usage, including:

• Setting thermostats no lower than 78 degrees
• Limiting the use of appliances during peak hours, and using washing machines, dishwashers and other heavy appliances only in the evening
• Closing drapes and blinds to keep rooms cool
• Ventilating homes at night and in the early morning to allow cool air to circulate
• Limiting the opening of refrigerators
• Turning off lights in unoccupied areas
• Relying on ceiling or smaller fans to cool rooms instead of air conditioners.