With parts of Los Angeles County still smoldering from wildfires, the expected rain this weekend would seem like a welcome relief. But how the rain falls could make the difference between a disaster respite or a disaster repeat.

Areas where the Palisades, Franklin, Eaton, Bridge, and Hughes wildfires burned are under a flood watch, the weather service said Sunday. Fresh burn scar areas stand at greater risk of mudslides because they no longer have trees and vegetation providing support to the land, according to AccuWeather Meteorologist Jacob Hinson.

Rain brought much needed aid to the Los Angeles firefight, moving the fires surrounding the city closer to containment.

The National Weather Service said there is a 15-25% chance of thunderstorms across the region, which could bring periods of heavy rainfall that could overwhelm the burn-scar areas.

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The blazes - named Laguna, Sepulveda, Gibbel, Gilman and Border 2 - flared up on Thursday in Los Angeles, San Diego, Ventura and Riverside.

"If fire ignition occurs, conditions are favorable for very rapid fire spread and extreme fire behavior," the NWS warns.

Weekend rains could bring some relief to Southern California. Here's the forecast and an assessment of how much it will help reduce fire risk.

NWS San Diego issues alerts for fire weather and a winter storm with snow and gusty winds in Southern California.

If the rain falls at a steady, lighter rate, Southern California could be in good shape. That could mean enough rain to help ease the firefighting strain, but not enough to trigger another potential disaster. Heavier rain could mean the chance for flash flooding or mudslides over fresh burn scars.

Rain was falling across Southern California on Sunday, bringing some relief to thousands of firefighters who have been battling multiple major wildfires in the LA area.