A brush fire burned in the hills above Pasadena during a day of heat and rain. Shanna Mendiola has the forecast for Thursday June 17, 2021.
Thunderstorms are possible Thursday in parts of Southern California during another day of excessive heat warnings.
More record highs will likely fall again Thursday as a high pressure system also transports monsoon moisture into the area that will help fuel thunderstorms. Lightning will be the biggest concern during a week of high fire danger.
NBCLA’s First Alert Radar picked up a few cells in Orange County Thursday morning. Strong winds are also possible.
Lancaster reached a high of 113 degrees on Wednesday, breaking the June 16 record of 111 degrees set in 1961. Palmdale reached 112 degrees, breaking the 1961 record of 110 and falling just one-degree shy of breaking the all-time record for June. Sandberg also set a record at 101 degrees, breaking the record of 98 set on June 16, 1961.
Get top local stories in Southern California delivered to you every morning. >Sign up for NBC LA's News Headlines newsletter.
The California Independent System Operator, which manages the state's power grid, has issued a Flex Alert for 5 to 10 p.m. Thursday, calling on residents to voluntarily reduce their power use to ease strain on the system and prevent possible power outages. Residents were urged to avoid using major appliances during the alert, turn off unnecessary lights and set thermostats at 78 degrees or higher.
Cooler conditions move in late Sunday, when all heat warnings are set to expire.
