Southern California storm arrives as communities brace for potentially dangerous flooding, debris flows

The first rainstorm in a series of wet weather has arrived in Southern California on Friday morning, bringing light rain, but it is only expected to intensify as the day goes on.

The National Weather Service said the atmospheric river is expected to produce at least 3-6 inches of rain across the region throughout the day and into Saturday.

Local officials have taken precautions ahead of the heavy rain, including the installation of extra K rails to divert possible debris flows and issuing evacuation warnings for high-risk areas, including recent burn scars.

One of the main concerns of the storm is potentially dangerous flooding. An NWS flood watch is in effect for much of Southern California through Saturday evening. The NWS said rain rates could be up to an inch per hour, which could cause excessive runoff.

An NWS flood advisory was issued Friday morning for the western part of LA County until noon. The agency said the Doppler radar indicated heavy rain due to thunderstorms and they are expecting minor flooding in low-lying and poor drainage areas. 

A CBS LA Next Weather Alert is also in effect through Saturday night for all communities. The purpose of the alert is to warn communities about a weather event that could cause disruption in their daily lives and commute.

The second part of the storm is expected to start Friday night, with the main intensity over Los Angeles and Ventura counties. Weather officials predict that between 6 p.m. Friday and 6 p.m. Saturday, 2-3 inches of rain will likely fall across flat portions of the coasts and valleys, and 2-4 inches of rain will fall across the coastal slopes.

"Rainfall rates will mostly be near a half inch per hour, but the heavier bursts will be near 1 inch per hour," the NWS said.

The rain will taper off Saturday night and by mid-morning on Sunday. Conditions should dry out on Sunday before another storm develops on Monday, bringing another chance of showers. 

Evacuation orders and warnings

There are several evacuation warnings in effect across most burn scar areas in Southern California.

Evacuation warnings are in effect in Ventura County near the Mountain Fire Burn Area and Matilija Canyon/North Fork, Camino Cielo area until 6 p.m. on Sunday. Storm advisories are also in effect for the communities of La Conchita and Camp Chaffee until 6 p.m. on Sunday.

Los Angeles County officials issued an evacuation warning for residents who live near the Kenneth Fire burn scar. The warning may also reach residents in the unincorporated areas of Oak Park in Ventura County, but the warning only applies to LA County residents.

Evacuation warnings are in effect in these LA County burn scar areas until 8 p.m. on Friday:

• Canyon
• Bethany
• Eaton
• Palisades
• Hurst
• Kenneth
• Sunset
• Lidia
• Franklin
• Bridge

According to LA County, after 8 p.m. on Friday, the advisories will be upgraded to mandatory orders for certain properties.  LA city officials said there are 126 homes affected by the evacuation order, which remains in effect until 8 a.m. on Sunday.

"Law enforcement personnel are in the field making door to door contact to notify these specific properties," LA County officials wrote. "Please follow all directions from field emergency responders throughout the duration of this event."

CBS LA was with members of the LA County Sheriff's Department as they went knocking on residents' homes in the Altadena area, telling them to be ready to evacuate if conditions become dangerous. 

Orange County issued evacuation warnings for the areas near the Airport Fire burn scar, including Trabuco Creek, Hot Springs Canyon and Bell Canyon. 

San Bernardino County issued evacuation warnings for areas near the Bridge and Line Fire burn scars.

Shelters 

The American Red Cross has opened three shelters in LA County:

• Stoner Park Recreation Center in Sawtelle: 1835 Stoner Ave, Los Angeles, CA
• College of the Canyons – 26455 Rockwell Canyon Rd., Valencia, 91355 
• Arcadia Community Park – 405 S Santa Anita Ave., Arcadia, 91006  

Road closures

Topanga Canyon Boulevard in the Palisades Fire Zone is closed due to the rainfall, according to Caltrans. The closure includes a 3.6-mile stretch of Topanga Canyon Boulevard/State Route 27 (SR-27) between Pacific Coast Highway and Grand View Drive. Officials said the road will remain closed until conditions improve. 

Where to get sandbags

With the forecasted weather, LA County Public Works has set up temporary sandbag distribution sites in fire-impacted areas where residents can pick up filled bags. 

• Public Works Fleet Maintenance Yard: 252 Mountain View St., Altadena, CA 91001  
• Malibu Library, Parking Lot: 23519 W. Civic Center Way, Malibu, CA 90265  

Residents must live in the community or city where they are requesting sandbags from. Proof of residency is required. 

Free ready-to-fill sandbags are also available year-round at all LAFD Fire Stations. Use this link to access a map of fire stations.