Temperatures could reach triple digits Monday in the San Diego County deserts, and the mercury will be on the rise all week throughout the region, according to the National Weather Service.
Conditions will be relatively mild west of the deserts Monday, but building high pressure will cause temperatures to rise throughout the county until Friday, forecasters said. By midweek, high temperatures could be 15-20 degrees above average in most areas, forecasters said.
The NWS issued a heat advisory that will be in effect from 10 a.m. Tuesday to 9 p.m. Friday in the western valleys.
An excessive heat watch will also take effect Tuesday morning and last until Friday evening in the county deserts.
The NWS urged residents to drink plenty of fluids, stay out of the sun and check up on relatives and neighbors.
Also, young children and pets should be never be left unattended in a vehicle, with car interiors able to "reach lethal temperatures in a matter of minutes," according to the NWS.
High temperatures Monday are forecast to reach 75 degrees near the coast, 77 inland, 84 in the western valleys, 83 in the mountains and 100 in the deserts.
Highs in the western valleys are expected to top out in the low- to mid-90s on Wednesday and Thursday, while the mercury in desert areas is projected to reach its peak at 108 on Thursday, forecasters said.
