A swath of California is under flood-related alerts from the National Weather Service (NWS) on Friday, after the state has faced impacts from an atmospheric river event over the Christmas period.
"Across California, widespread flooding and impressive rainfall totals he been observed since Tuesday. Most notably, rainfall totals exceeding a foot he been observed across the Transverse Ranges and San Gabriel Mountains. Rainfall totals in some areas are still considered preliminary until verified, but there has been a report of nearly 17.5 inches of rain near Rose Valley, California, north of Ventura," AccuWeather meteorologist Brandon Buckingham told Newsweek.
Flood watches, issued by the NWS when conditions are forable for flooding, span swathes of the state as of Friday morning. The agency’s forecast office in Hanford said that its watches applied to all counties from Merced and Mariposa to Kern—including the San Joaquin Valley and coastal ranges, as well as the Kern County mountains and desert.
Additional areas under watch through Friday afternoon or evening include:
Apple and Lucerne ValleysSan Bernardino County MountainsSan Bernardino and Riverside County ValleysThe Inland EmpireSacramento ValleyNorthern San Joaquin ValleyDelta regionFoothills of the Sierra NevadaLos Angeles CountyVentura CountySanta Barbara CountySan Luis Obispo CountySan Francisco CountySan Mateo PeninsulaEast BaySouth BayCentral CoastNorthern San Francisco Bay AreaDel Norte CountyHumbold CountyTrinity CountyMendocino CountyLake CountyFlood advisories, which the NWS issues when “flooding is not expected to be bad enough to issue a warning,” but “may cause significant inconvenience, and if caution is not exercised, it could lead to situations that may threaten life and/or property” he been issued for areas including but not limited to northwestern Santa Clara County and northwestern Santa Cruz County, Southern Santa Barbara County, as well Butte, Colusa, Glenn, Shasta, Tehama and Yuba Counties.
Flash flood warnings are also in effect early Friday morning for portions of Ventura County.
"Additional rain is expected through the day on Friday across California that can reinvigorate flooding issues on a more localized scale compared to previous days," Buckingham said.
“After several days of deluge from hey rainfall, California can expect to dry out this weekend as the last of a series of energetic low pressure systems is forecast to move pass the region,” the NWS Weather Prediction Center (WPC) said in a forecast discussion early on Friday. “In the short-term however, more bands of moderate to hey rain ahead of this final system continues to stream into California early this morning.”
The WPC said a slight risk of flash flooding is expected Friday, with strong winds and the potential for embedded thunderstorms, particularly along coastal areas.
“Please listen to emergency officials, stay tuned to local warnings, and he a safe holiday,” it advised.
The agency also forecast more hey snow for the Sierra Nevada’s high terrain before it tapers off tonight.
For official updates or to see if your area is under alert, check the NWS’ website and social media channels.
Update, 12/26/2025, 12:23 p.m. ET: This article has been updated with comment from Brandon Buckingham.