Rain could begin falling across the Conejo Valley as early as late Tuesday, Oct. 20, with the heaviest storm activity expected Wednesday and Thursday.

The National Weather Service forecasts showers on Wednesday, Oct. 21, with an 80% chance of precipitation and a quarter to half inch of rain during the day, according to Ventura County Emergency Management. The NWS forecast for Thousand Oaks shows a 100% chance of precipitation Wednesday night, with a half to three-quarters of an inch of new rainfall and a chance of thunderstorms.

Showers remain likely Thursday, Oct. 22, with a 70% chance of rain and possible thunderstorms before skies clear Thursday night.

Temperatures will drop sharply. Thousand Oaks is expected to reach 77 degrees Tuesday before falling to 66 on Wednesday and 65 on Thursday, according to the NWS.

Street flooding and burn-area danger

Ventura County Emergency Management warned that heavier rain could cause localized street flooding and hazardous driving conditions. Residents near recent wildfire burn areas should stay alert for flooding and debris flows, the county said.

The Bryson Fire, which started Oct. 15 near Encinal Canyon Road in Malibu, burned 147 acres and was 74% contained as of Oct. 18, according to CAL FIRE.

The Ventura County Star first reported Oct. 12 that county officials had identified vulnerable spots ahead of a potential super El Niño season. Agencies set a debris-flow trigger threshold of 0.6 inches of rain per hour for areas burned in the Sandy Fire near Simi Valley, the Star reported.

Patrick Maynard, director of the Ventura County Sheriff's Office of Emergency Services, told the Star that officials "will need to monitor that area very closely."

La Conchita landslide warning

A Hazardous Weather Advisory remains in effect for La Conchita, the coastal community off Highway 101 north of Ventura. The county said cumulative rainfall near La Conchita has exceeded historical landslide triggers, and geological conditions resemble those that contributed to significant damage in 1995 and 2005.

County officials are strongly encouraging La Conchita residents to seek shelter elsewhere. The county has deemed the community a geologic hazard area and advises against entry under any circumstance.

Beach hazards

A Beach Hazards Statement is in effect for Ventura County beaches through late Thursday night. The NWS expects surf of 3 to 6 feet and dangerous rip currents along Ventura County, Malibu Coast and Los Angeles County beaches.

The NWS warned that waves can wash people off rocks and capsize small boats nearshore.

Road closures and resources

Residents can check road conditions through the Ventura County Public Works Agency website for county-maintained roads and through Caltrans or CHP Traffic for state highways.

Several self-serve sandbag locations are available 24/7 across Ventura County, including fire stations and parks. Residents with questions about sandbag sites can call the Parks Division at (805) 385-7950.

To sign up for emergency alerts, visit readyventuracounty.org/vc-alert.