Josephine Peak is set within San Gabriel Mountains National Monument, approximately six miles (9.7 km) north of the community of Altadena and 18 miles (29 km) north-northeast of downtown Los Angeles.

Topographic relief is significant as the summit rises 2,450 feet (747 meters) above Clear Creek in approximately one mile.

Hiking to the summit involves eight miles of trail with 2,100 feet of elevation gain.

[8] Most weather fronts originating in the Pacific Ocean travel east toward the San Gabriel Mountains.

As fronts approach, they are forced upward by the peaks (orographic lift), causing them to drop their moisture onto the range.