As of early Friday morning, the National Weather Service has posted a winter weather advisory that includes the Riverside County Mountains, which remains in effect through Saturday.
The NWS forecasts a cold, low pressure trough will move across southwestern California tonight through Saturday. The system is likely to generate a period of moderate snow in the higher elevations of the mountains, such as Mt. San Jacinto State Park. The heaviest snow is most likely Saturday morning and improving conditions on Sunday.
From late Friday through Saturday, snow accumulations could total 1 to 3 inches above 6,500 feet. However, snow may fall as low as 6,000 feet beginning Saturday morning, according to the NWS.