Temescal Valley (Temescal, Spanish for "sweat lodge") in California is a graben rift valley in western Riverside County, California, a part of the Elsinore Trough.
It is a complex graben, divided lengthwise into several smaller sections by transverse faults.
The Temescal Valley is one of these graben, at the northern end of the trough.
The Temescal Valley graben is bounded northeast side by the Lee Lake longitudinal fault and similarly on the southeast by the Glen Ivy Fault.
According to the Geographic Names Information System the valley head lies just west of Lee Lake, between the Santa Ana Mountains and the Temescal Mountains to the east, and runs to the vicinity of the confluence of Temescal Creek with Brown Canyon Creek where the mountains closed in to create a narrows.