A slow-moving storm system is expected to reach the Southland tonight, but forecasters said it is unlikely to trigger debris flows, even over areas denuded by wildfires.

The rain likely will last through Wednesday, the first day of Spring 2019.

Long Beach has a 50 percent chance of showers and thunderstorms after 11 p.m. tonight with showers likely and a possible thunderstorm after 11 a.m. Wednesday, according to the National Weather Service.

The weather service has also issued a high-surf advisory for Long Beach through Thursday.

Snow is likely in the San Gabriel Mountains, and there will be a slight chance of thunderstorms, according to an NWS statement.

“Partial clearing is expected Thursday into Friday, with a slight chance of light rain Friday night through Saturday,” it said.

Forecasters said there remains uncertainty regarding rainfall amounts due to the expected showery nature of the storm and the possibility of thunderstorms. But in general, amounts should range between a tenth and a quarter of an inch in Los Angeles County, with a quarter-inch and a half-inch possible. Up to an inch is possible in heavier showers or thunderstorms.

Rainfall rates should stay under a quarter-inch per hour but could top out at a half-inch anywhere in a thunderstorm.

“The threat for debris flows are minimal. Impacts will likely stay confined to travel issues from wet roads,” according to the statement.

The snow level is expected to remain in the 5,000-to 6,000-foot range but could drop to 4,000 feet Wednesday morning in the most unstable air mass. We could see a dusting of snow on some mountain roads, but accumulations should stay above 5,500 feet, according to the statement.

Some gusty south winds are expected today into early Wednesday but they may be under advisory-strength. A wind advisory points to winds or gusts of 35 mph.

“Due to the slow movement of the system, we could still see scattered showers anywhere on Thursday,” the statement said, “and temperatures will remain below normal.”

Showers with a dusting of snow on mountain roads are possible on Thursday, forecasters said. Gusty northwest winds will create difficult driving conditions. High surf and dangerous rip currents are expected over the weekend.

Along the Southland coast, a high-surf advisory will be in force from 5 a.m. Wednesday to 3 p.m. Thursday, with surf of 4-7 feet pounding the shore.

“Minor coastal flooding is possible over low-lying coastal areas such as beach parking lots and bike pathways,” warned an NWS statement. “There is an increased risk for ocean drowning. Rip currents can pull swimmers and surfers out to sea. Large breaking waves can cause injury, wash people off beaches and rocks and capsize small boats near shore.”