Authorities were urging anyone who lives in the area along the Orange and Riverside county line that was left charred by the Holy Fire last summer to evacuate on Tuesday, ahead of heavy rain expected to hit the area later in the week.
More than 4 inches of rain may fall in inland Southern California mountain areas, including hillsides in the Cleveland National Forest that were stripped of their topography in the August blaze, making them susceptible to mud and debris flows.
An flash flood watch is in effect for burn scar areas — including inland Orange County, Riverside County mountains, San Bernardino County mountains and the Santa Ana Mountains and foothills — from Thursday morning through Thursday evening, the National Weather Service said.
Although the rain is forecast to begin falling Wednesday evening, it will become more intense the following day, with a rate of half an inch or more per hour possible, according to the weather service.
Strong winds are also expected to be a factor, with gusts of up to 75 mph in mountain areas and on desert slopes, and motorists were urged to use caution on the interstates 8, 10 and 15.
Officials issued a voluntary evacuation warning for residents in the Amorose, Alberhill, Glen Ivy A, Glen Eden, Grace, Horsethief A, Laguna A, Matri, McVicker A, Rice and Withrow A zones.
"People in these zones SHOULD GO NOW because it is the safest time to leave," Riverside County emergency officials said in a news release.
"Because debris flows can happen with little to no warning, emergency officials might only be able to provide residents a few minutes’ notice, or none at all," the release continues. "As always, residents are urged to remain vigilant and take personal responsibility for their safety."
Residents can determine their evacuation status by visiting www.RivCoReady.org/StormReady and scrolling down to the zone maps. Some boundaries have changed since previous evacuation warnings, so residents should be sure to verify which zone they live in, authorities said.
An evacuation center was set up at Temescal Canyon High School, located at 28755 El Toro Road in Lake Elsinore. Animals both large and small could be taken to the San Jacinto Animal Campus at 581 S. Grand Ave. in San Jacinto.
In addition to the Holy Fire area, flash flooding and debris flows could hit areas impacted by the Cranston Fire, Valley Fire and Canyon 1 and 2 fires, NWS said.
There were no evacuations in the area south of Idyllwild that was scorched by the Cranston Fire, but emergency officials were still warning residents to stay away from burn areas and remain aware of their surroundings.
For more information or to register for emergency alerts, visit www.RivCoReady.org.