According to the Mariposa Gazette:
A large boulder slid onto the east bound lane of [Highway 140] approximately one mile from the [Briceburg Grade] late Monday afternoon. CHP and Cal Trans are on scene for traffic control.
A closure expected to last hours has not yet been announced as equipment must be transported from Merced to handle the situation. Traffic delays should be anticipated.
I’ve been waiting for this to happen all day. Loyd predicted this to me this morning.