Southern California's weather turned from dangerously dry to extremely wet Friday as a storm dropped rain on areas burned in recent wildfires, raising the threat of flash floods and mudslides. Sheriff's deputies in Orange County prepared to go door-to-door in burned areas in Modjeska and Williams canyons to advise people of a voluntary evacuation recommendation due to the risk of mudslides, said Lt. Ted Boyne. Deputies were starting with about 300 homes but were assembling teams of deputies in case they needed to alert homeowners in nearby Trabuco and Silverado canyons as well, he said. Another team of deputies was patrolling the canyons looking for signs of trouble. A flash flood warning was posted in north-central San Diego County where the Poomacha and Rice wildfires of late October left thousands of acres barren. One gauge just outside the burn area had recorded more than 2 inches of rain by midday, with more to come, the National Weather Service said.