In the forecast for Wednesday were highs of 72 to 77 degrees at the beaches, 80 to 85 degrees in inland coastal areas, 84 to 89 degrees in the western valleys, 93 to 98 degrees near the foothills, 93 to 101 degrees in the mountains and 111 to 116 degrees in the deserts.
A National Weather Service heat advisory for the deserts and mountain areas higher than 6,000 feet is set to expire at 8 p.m. A beach hazards statement warning of 3- to 6-foot surf, sets to 7 feet and strong rip currents will remain in effect from noon today to Friday evening.
“High surf along with strong rip and longshore currents will create very hazardous swimming conditions,'' according to the weather service. “Rip currents may pull swimmers out to sea. Sneaker waves can suddenly wash people off rocks and jetties.''
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Beachgoers were advised to obey warning signs and swim near a lifeguard. Those not headed to the beaches should avoid potentially serious heat-related ailments by staying well-hydrated, avoiding unnecessary outdoor labor and checking on neighbors and relatives -- especially those with health conditions, who lack air conditioning, and the elderly.
The county's “Cool Zones'' program has designated more than 115 air- conditioned buildings as public cooling centers. Locations and hours of operation can be found online via an interactive map at CoolZones.org, or by calling the 2-1-1 San Diego telephone service.
Authorities also warned against leaving children or pets in parked cars, which can quickly become death traps in high heat.
Forecasters said temperatures are expected to lower into the weekend. Saturday and Sunday will likely the coolest days with temperatures generally closer to normal.
“One more very hot day is on tap away from the coast today, then gradually becoming cooler into the weekend, with a slowly building marine layer,'' according to the weather service.