Southern California is set to experience a shift in weather starting Friday, with cooler, cloudier conditions and the potential for rain and mountain snow. After a few days of fair weather with temperatures slightly above average, a low-pressure system will move in Thursday night, bringing gusty winds and precipitation through Saturday. Snow levels are expected to drop to around 5,000 feet on Friday, possibly dipping to 4,000 feet on Saturday, creating conditions for snow at higher elevations. Coastal and valley areas could see light rainfall, with a 20-30% chance of totals reaching a quarter-inch. The mountains may experience stronger winds with gusts of 40-55 mph. Cooler temperatures are expected to last into early next week, with more rain possible by Monday. Dry conditions should return by Tuesday.