Seasonal temperatures will continue Thursday throughout San Diego County, but the mercury will rise quickly on Friday and highs could reach the triple-digits this weekend in several areas, according to the National Weather Service.
High pressure centered over New Mexico and Arizona will strengthen and expand starting Friday and continuing through Monday, forecasters said.
Triple-digit heat is expected in the western valleys and the San Diego County mountains on Saturday and Sunday, while highs in the county deserts could soar past the 120 mark those two days, forecasters said. Sunday is expected to be the hottest day of the heat wave, with highs potentially reaching 121 in the deserts, 104 in the mountains and 102 near the foothills of the western valleys.
The NWS issued an excessive heat warning that will be in effect from 10 a.m. Saturday through 8 p.m. Monday in the deserts.
NWS officials urged residents to drink plenty of fluids, stay out of the sun and check up on relatives and neighbors. Also, young children, senior and pets should be never be left unattended in a vehicle parked during the day, with car interiors able to reach lethal temperatures in minutes.
High temperatures today are forecast to reach 76 degrees near the coast, 83 inland, 86 in the western valleys, 93 near the foothills, 96 in the mountains and 112 in the deserts.
Slight cooling will arrive in the deserts on Tuesday and continue through at least Wednesday, forecasters said.
