The first big storm of the season is expected to bring rain to Southern California on Wednesday, raising fears of mudslides and flooding in parts of Los Angeles, Orange, Ventura and Riverside counties recently impacted by wildfires. There are also concerns about rock slides on canyon roads.

Spectrum News 1 meteorologist Robert Santos says scattered showers will likely arrive during the latter part of the afternoon commute, with more rain coming throughout the night.

The Riverside County Emergency Management Department has posted a flash flood warning along with a recommendation for voluntary evacuations.

The county has also recommended evacuations in parts of Lake Elsinore along Alberhill Ranch Road and Amorose Street, as well as for residents of Glen Eden Road south of Corona, the Glen Ivy Hot Springs community, the Horsethief Canyon community and areas around McVicker Park in Lake Elsinore.

Although no mandate has been issued, voluntary evacuations are also underway in parts of Orange County that include Trabuco Canyon, Rose Canyon, Mystic Oaks and El Cariso.

Rainfall of between a half-inch to two inches is expected in the impacted areas with higher elevations facing as much as three inches of rain.

In Los Angeles County, the rain could start coming down Wednesday evening and is likely to increase overnight into Thursday morning. 

Rain is also likely to fall on areas stripped of vegetation by the Woolsey fire in L.A. and Ventura counties, the Hill fire in Ventura County, and the Thomas Fire, which raged through Ventura and Santa Barbara counties in December of 2017. Residents in areas affected by the Holy Fire earlier this year in Orange and Riverside counties are also urged to take precautions.

Additionally, Malibu residents have been urged to prepare for potential flooding, mudslides, power outages, and evacuations.

City News Service contributed to this report.