Topline:
The National Weather Service says that starting today, Southern California will see its hottest heat wave of the summer so far.
The details: Temperatures are expected to be in the high 90s and low 100s in inland areas through the weekend. The hottest days will be on Thursday and Friday. Woodland Hills, for example, could see a high of 108.
Keep reading...for tips on how to prepare and stay safe.
Extreme heat is expected to bear down on Southern California starting Wednesday in what meteorologists are calling the most significant heat wave of the summer.
For the rest of the week, temperatures are expected to be 10 to 15 degrees hotter than normal across the region, prompting warnings from public health officials to take precautions.
“ This is a serious situation,” said Ariel Cohen, a meteorologist with the National Weather Service. “ It's time now to start preparing, have a lot of water on hand, drink plenty of fluids, stay in an air conditioned rooms.”
It’s also a good time to check on neighbors, Cohen said, and to remember this key safety tip: Never leave kids or pets in the car or unattended for any amount of time in the heat.
The city of Los Angeles is also extending hours at several senior and recreation centers in the hottest neighborhoods as “cooling centers.” (For more information, go here.)
A cooling center is any public place with air conditioning, including libraries and community centers. There are also of course the tried-and-true options: beaches, pools and malls.
Here’s what forecasters say you should expect:
Still on track for an extended period of hot weather this week, and this threat will be combined with a high risk for large fires where watches & warnings are in effect. There is also a chance of tstms from Fri-Sun, which can create lightning triggered fires & localized flooding. pic.twitter.com/ei20kpGfzW
— NWS Los Angeles (@NWSLosAngeles) August 18, 2025
Cohen said with temps this extreme, the risk of heat related illnesses and fatalities goes up.
“There's going to be high risk for dangerous heat illnesses for anyone, especially for the very young, the very old, and those without air conditioning,” Cohen said.
Thunderstorms are also potentially on the horizon late this week into the weekend. That could cool things down, but it also raises the risk of local flooding and fires sparked by dry lightning.
Southern California is back in a drought, and vegetation is extremely dry. Add in hot weather and it’s a recipe for wildfires, Cohen said. In Southern California, this is the usual time for fire season, which historically extends from late spring through October. In recent decades, human-caused climate change has extended fire season, including deep into winter, such as what we experienced with the devastating Eaton and Palisades fires.
“We can get explosive fire behavior if a fire forms in a very hot, unstable environment,” Cohen said. “So once a fire takes off, it pretty much develops a [weather] system of its own and can grow explosively and rapidly, even if the winds aren't that strong.”
In anticipation of the fire risk, Gov. Gavin Newsom on Tuesday deployed a contingent of firefighting resources to be on standby, including fire engines, bulldozers, aircraft and hand crews to Los Angeles County.
Red flag warnings are in effect for the mountains and foothills of Los Angeles and Ventura counties, and Cohen said the National Weather Service is “closely monitoring other areas in Santa Barbara and San Luis Obispo counties for the potential for explosive fire growth as we head into late this week.”
That all means now is the time to prepare for potential fires, how to evacuate safely and what to do if there are power outages.
Things should start to cool down slightly by early next week, though thunderstorms will still be a risk, Cohen said.