San Diego was under a heat advisory Wednesday due to record-breaking heat, high humidity and thunderstorms.
The National Weather Service issued the advisory -- set to expire Thursday at 6 p.m. -- for residents living along the coast and in the inland valleys.
Wednesday marked the hottest day of the summer for San Diego, with temperatures at Lindbergh Field reaching 92 degrees. Granite Hills High School in El Cajon canceled all after-school practices and activities due to the extreme heat.
Temperatures at the beaches climbed into the upper 80s and felt closer to the low 90s, as moisture associated with Hurricane Linda surges into Southern California.
Inland valleys will see temperatures climb into the upper 90s, which will feel like the low triple digits.
Residents should seek cool zones, wear light or loosefitting clothes and drink plenty of water to avoid heat related illnesses. Seek medical attention if you start to feel nauseated or dizzy. Heat stroke can come on unexpectedly and can be fatal.
Click here to find a cool zone near you.
A senior center in Chula Vista, which is a designated cool zone, became a popular place Wednesday for many trying to beat the heat. Those who spoke with NBC 7 complained of the humidity, likening it to weather you'd find on the East Coast, not Southern California.
"I don't have central air," said Edna Monk, who was spending her day at the cool zone. "I have window air conditioners that, with this kind of weather, really doesn't cut it."
Others had no choice but to be in the heat. Construction workers sweated in the sun as they laid down pipes. Worker Gilbert Hernandez said he loves his work no matter the weather.
"I'm used to this. This is what I like to do," he said. "I'd like to be inside right now, off of work, but this is what I do."
A flash flood watch was issued for San Diego mountains, as slow-moving thunderstorms could produce heavy rainfall, hail, strong winds and flooding.
Never attempt to drive through moving water. In the presence of thunder and lightning, head indoors.
Thursday will be even hotter, with a 20 percent chance of thunderstorms, even at the coast and in the valleys. Friday begins a slight cool down which will be more significant relief next week.