An atmospheric river was set to begin pummeling Southern California with heavy rain on Thursday, prompting evacuations and school closures as officials warned about life-threatening flooding and mudslides in areas charred by the wildfires that broke out across the region last month.

An intense storm could cause flooding and debris flows in areas burned by wildfires. Some residents have begun to evacuate.

Officials in California distributed sandbags, prepositioned rescue swimmers and told residents to have their go-bags ready as the state prepares for an atmospheric river that could bring heavy rain, winds and flooding Thursday to areas ravaged by wildfires.

Forecasters said excessive rainfall could lead to flash flooding and debris flows in recent burn scars, including the Eaton and Palisades fires.

Evacuation orders and warnings have gone into effect for burn scar areas across Southern California as heavy rainfall threatens dangerous debris flows.

A winter storm, anticipated to be the strongest of the season to date, began dropping water over Southern California overnight into early Thursday morning, bringing a half-inch of rain to some areas in Orange County, the Inland Empire and the Los Angeles County mountains by sunrise.

Southern California is in desperate need of rain, but it could come far too fast this week, especially in areas recently burned by wildfires.

What to Know The brunt of the storm will bring widespread rain starting Thursday morning with peak intensity expected later in the day. A flash flood watch went into effect for much of the region Thursday morning and will continue into the night.

Flood watches, when flooding conditions are considered ripe, are in place for stretches including the burn scars surrounding the Eaton, Palisades, Franklin and Bridge fires, from 1 p.m. Thursday, Feb. 13, to 4 a.m. Friday, Feb. 14.