Heat advisory expands as humidity pushes temperatures higher

Southern California is bracing for a heat spell expected to peak Wednesday, paired with higher-than-average humidity. A heat advisory runs from 8 a.m. Tuesday until 9 p.m. Thursday across multiple areas, with temperatures climbing into the 80s and 90s and a th

For the rest of the week, Southern California’s usual summer routine could feel different—heavier in the air, harder to ignore, and more dangerous for people who already struggle in the heat.

The National Weather Service says the hottest period is expected to peak on Wednesday, and that it won’t just be temperatures doing the work. Forecasters are warning that higher than average humidity will make conditions feel warmer than what the thermometer suggests.

“The humidity is going to make the weather a few degrees warmer than the standing temperature,” National Weather Service meteorologist Devin Black said.

On Wednesday, temperatures are expected to reach into the middle to upper 90s in the San Gabriel and San Fernando valleys. In the Los Angeles basin—covering places including Inglewood and Downtown Los Angeles—the forecast calls for low to mid 80s.

The heat is also expected to carry added risk for sensitive groups, including “the very young, elderly and those active outdoors and without air conditioning,” Black said.

Evenings may offer some relief, but not a full reset. After Thursday, temperatures are expected to cool down, but they will still stay above average through the weekend.

The weather service is also flagging storm potential as the heat builds. Black said there is a threat of thunderstorms, especially Tuesday going into Wednesday across Los Angeles County.

A heat advisory is already in effect, running from 8 a.m. Tuesday until 9 p.m. Thursday for the eastern San Fernando Valley, eastern San Gabriel Mountains, Santa Clarita Valley, western San Fernando Valley, western San Gabriel Mountains and the Highway 14 corridor.

The warning comes with straightforward steps meant to prevent heat exhaustion and heat stroke. The weather service advises locals to drink plenty of fluids, stay in an air-conditioned room, stay out of the sun, and check up on family members and neighbors.

The advisory urges people to “Take extra precautions when outside,” “Wear lightweight and loose fitting clothing,” and “Try to limit strenuous activities to early morning or evening.” It also says people should “Take action when you see symptoms of heat exhaustion and heat stroke.”

By Thursday, the worst of the heat should ease. But with humidity adding an extra layer of strain—and warm conditions hanging around through the weekend—the message from the weather service is clear: don’t wait for it to feel dangerous before taking precautions.

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