According to the National Weather Service, periods of moderate to heavy rain are expected through Monday afternoon and could trigger flash flooding and mudslides in fire zones.

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

Southern California’s first rainy weekend of the winter has arrived. The rain event, months in the making, brought steady storms across the region as the Southland experiences drought conditions. The mostly welcome rain began Saturday night and is expected to sustain until Monday evening.