The National Weather Service issued a flood advisory for northwestern Riverside County and southwestern San Bernardino County until 5:30 p.m. Forecasters say more wild weather could come on Friday.
The mid-afternoon storm dumped a lot of rain in a short amount of time. The flooding affected Riverside Community College. Some students were able to drive away from the waterlogged parking lot after wading to the driver's seat.
Around 1 p.m., a strong storm cell moved in along Highway 38 in Forest Falls. Water came rushing across the road. County public works crews were out in force, making sure there weren't a lot of rocks on the highway.
Gail Forgues of Forest Falls got the alert on her phone about the thunderstorm warning. She likes the summer rain, but doesn't want things to get out of hand.
"The other day it was a better rain storm, it was gentle, steady. This, it just starts the flooding and the running of water," said Forgues.
The area also saw hail. It only lasted for a couple of minutes, but it showed how intense the storm was at one point.
The storm also knocked down trees and power lines. Middle College High School in San Bernardino said it was canceling back-to-school night due to a power outage.
Riverside Public Utilities said 10,000 customers were without power in the Riverside area at one point. Crews restored power to about half of the customers around 6 p.m. They said it could take up to 24 hours to restore the rest of the power. Downed trees and traffic slowed down the process.
Greg Zimmerman of Riverside arrived home to find some unexpected pruning on his street. Strong winds severed tree limbs and uprooted a large tree on Ramona Drive.
"Seeing all the palm trees and the branches broken down, we felt like we were in another part of the country," said Zimmerman.
When the rain cleared, the heat and humidity returned. Some were happy about that. But for others, given how hot it has been, they were hoping for rain.
Some people had fun in the rain. Over on 14th Street, near the 91 Freeway off-ramp, several feet of water covered the road. The closed-off intersection enticed daredevil John Francis to jump in. He made his partial cannonball plunge off the bridge unconcerned about the potential risk involved.
"You only get to jump in Lake 14th Street once. So I was just, 'Hey, why not?' It was nice. It was a little bit cold, dirty. It was fun," said Francis.