The mercury will continue to rise this weekend in San Diego County's western valleys, mountains and deserts as a result of a heat wave that will keep those areas scorching until Monday, according to the National Weather Service.
A strong system of high pressure has been building over Arizona and New Mexico, ushering in sweltering heat in most of Southern California through Monday, forecasters said.
The National Weather Service issued an excessive heat warning that will be in effect from 10 a.m. today through 8 p.m. Monday in the deserts, while a heat advisory will last from 10 a.m. today through 8 p.m. Sunday in the western valleys and the mountains.
NWS officials urged residents to drink plenty of fluids, stay out of the sun and check up on relatives and neighbors. Also, young children, seniors and pets should never be left unattended in a vehicle parked during the day, with car interiors able to reach lethal temperatures in minutes.
High temperatures for Saturday are forecast to reach 82 degrees near the coast, 86 inland, 89 in the western valleys, 98 near the foothills, 98 in the mountains and 110 in the deserts. Sunday's high could reach 120 in some desert communities.
Slight cooling will arrive in the deserts on Tuesday and continue through Thursday, forecasters said.