At least 13 people have been killed by a Southern California storm that brought flash floods and mudslides, with authorities in Santa Barbara County trying to reach new areas to find dead, injured or trapped people after a mudslide swept away dozens of homes. Most of the deaths were believed to have taken place in the wealthy enclave of Montecito. There were also 20 people hospitalized, four of them in "severely critical" condition. Authorities had been bracing for the possibility of catastrophic flooding because of forecasted heavy rains for the first time in 10 months, which were arriving after the recent wildfires. Burned-over areas are particularly susceptible to mudslides because the burned ground doesn’t absorb water well. Evacuations had been ordered below recently burned areas in Santa Barbara, Ventura and Los Angeles counties, but only some 10 to 15 percent of people in a mandatory evacuation area of Santa Barbara County listened to the warning.