The National Weather Service issued a flash flood warning for western Placer County and south central Nevada County on Thursday as the region was pelted with heavy rain.
The warning was issued just after 3 p.m. and set to last until 6 p.m. after thunderstorms were spotted near the Sierra Nevada.
The weather service warned of small hailstones in addition to the rain but predicted the storms would stay in the foothills and mountains.
By 3:20 p.m., the weather service was reporting a foot and a half of water in the westbound lane of Interstate 80 near Colfax.
The affected area could see as much as 2 inches of rain in an hour, according to the weather service
“If you are in the warned area move to higher ground immediately,” the agency said in its warning. “Residents living along streams and creeks should take immediate precautions to protect life and property.”