Southern California faces heightened risks from the forecasted strong El Niño, including flash floods, debris flows in burn scar areas, severe thunderstorms, and coastal flooding. Beach erosion and dangerous rip currents could also pose threats to coastal communities. Vulnerable hillsides and erosion-prone areas are being assessed by city engineers to mitigate potential damage. Residents are advised to remain vigilant, especially in areas with burn scars, as these are particularly susceptible to debris flows during heavy rains.