The CHP closed all lanes of traffic in both directions between the off-ramps at Mowry and Thornton avenues around 3:30 a.m. All lanes were reopened around 9 a.m.
LIVE: Track rain in San Francisco Bay Area with Live Doppler 7
At least half a dozen drivers saw their cars stranded in high water on the freeway
"We started getting calls and our officers started saying early on this is going to be bad later," said CHP Officer Dustin Kennerly.
The conditions this morning were so bad that numerous accidents occurred, including one car that flipped all the way on the roof.
"Slow down and make sure your headlights are on, give yourself extra distance. Any less accidents we can deal with today we would appreciate it," said Officer Kennerly.
POWER OUTAGES: Latest PG&E Information
EVACUATIONS: List of Bay Area evacuations
BUSINESS CLOSURES: Bay Area storm causes closures for Oakland Zoo, Alameda County Fair
RELATED STORIES & VIDEOS:
- VIDEO: Watch the latest AccuWeather forecast
- How to prepare your home for winter storms
- TIPS: How do you recover from hydroplaning?
- Tips for how to drive safely on rainy days
- TIPS: Here's how to use sandbags and prevent flooding