Much-need rain has begun to fall over Southern California, bringing relief to the drought-stricken region but also the threat of toxic runoff.

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.

Southern California is expecting up to an inch of rain in some parts, aiding the fight against wildfires but also causing landslides that threaten homes in Los Angeles area. NBC News' Steve Patterson reports on the anxieties residents face as they try to resettle.