Temperatures will gradually rise over the weekend before peaking on Monday and Tuesday, according to the National Weather Service.
High pressure will slowly build over the weekend and result in high temperatures that measure about 5-10 degrees above seasonal averages on Monday and Tuesday, forecasters said.
Smoke from nearby wildfires will be visible Friday in the San Gorgonio Pass near Banning but should clear by Friday evening, according to the NWS.
Highs in the Coachella Valley are expected to climb to 105 on Saturday, then 108 on Sunday, according to the NWS. The mercury in the Riverside metropolitan area is forecast to top out at 103 on Tuesday.
High temperatures Friday could reach 101 degrees in the Coachella Valley, 92 in the San Gorgonio Pass near Banning, 94 in Riverside, 91 in Lake Elsinore, 92 in Temecula and Hemet and 77 in Idyllwild.
A trough of low pressure is expected to arrive by midweek next week and bring cooler temperatures, forecasters said.