National Weather Service (NWS) meteorologists issued a flood warning in Sacramento, California, on Tuesday morning as the Sacramento River hit a depth of 210.7 feet at the Tehama Bridge, putting it into minor flood stage.
The rising water levels come as California has faced a slew of atmospheric rivers that brought a deluge of moisture across the state. Although the strong storm systems have moved on, lingering flood impacts are expected to continue as further rain and water run-off contribute to surging river levels.
Atmospheric rivers are a “long, narrow region in the atmosphere—like rivers in the sky—that transport most of the water vapor outside of the tropics,” according to the National Oceanic and Atmospheric Administration (NOAA).
NWS Sacramento issued the flood warning at 6:49 a.m. Pacific Standard Time. Impacts are expected to persist for up to seven hours.
“Recent rain and runoff is causing Tehama Bridge along the Upper Sacramento River System to reach Minor Flooding Stage this morning,” NWS Sacramento said in the flood warning. “Forecast keeps the Tehama Bridge in Minor Flooding for the next five to seven hours, then return to Action/Monitor Stage later this afternoon.”
Newsweek has reached out to NWS Sacramento by phone for comment.
The river is currently measured at 210.7 feet, a level in which “the county park becomes inaccessible,” the warning said.
“At 211 feet water begins to enter Driftwood RV fishing resort on east bank of river and just north of the county park,” the warning said.
Flood stage, or when water levels rise high enough to submerge areas not typically underwater, occurs when the river is at 209 feet. Minor flood stage is the next level of flooding that occurs after flood stage.
“Motorists should not attempt to drive around barricades or drive cars through flooded areas,” the flood warning said. “Turn around, don’t drown when encountering flooded roads. Most flood deaths occur in vehicles.”
According to data from the Office of Water Prediction, the river has already crested at 211.03 feet and is now declining. The flood warning was issued after the river rose around 5 feet in only 12 hours. The river is expected to fall below flood stage Tuesday afternoon and continue falling to 203.3 feet Thursday morning.
The storms brought by atmospheric rivers are known for their heavy snow, rain and strong winds. They more commonly affect the West Coast, particularly during the winter months. Although the storms can bring beneficial snow that helps supplement reservoirs throughout the summer dry season, they can also trigger deadly flooding, mudslides and widespread power outages.
Over the past six days, the Sacramento area received 2 inches of rain, according to a post on X by NWS Sacramento. Flood warnings also have been issued by the NWS offices in Eureka and San Francisco.