Record Set as Heat Wave Rolls On : Scorcher: Heat sparks brush fires that blacken over 1,500 acres in the county. Water and electric use soar.

San Diego County sizzled under record-breaking heat Wednesday as electricity usage soared to new heights and beleaguered lifeguards continued to rescue scores of overheated swimmers from tricky Pacific rip currents.

Brush fires, fueled by gusting winds, burned nearly 1,200 acres in North and East San Diego County.

Searing heat broke longstanding records across Southern California and the rest of the Southwest for the second straight day Wednesday.

The parching heat and gusting winds generated a massive inland high-pressure system, hampering the efforts of firefighters battling blazes that destroyed at least 14 homes in canyons in Glendale and near Yorba Linda in the Los Angeles area.

The crippling heat wave has been blamed for several deaths. A 4-year-old boy died of heat exhaustion Tuesday after being accidentally locked in a parked car in Pacoima, in the San Fernando Valley. Heat stroke is suspected in the deaths of three people in Phoenix on Tuesday, where it was 122 degrees. In addition, five firefighters were killed Wednesday in Arizona while battling a fire set by lightning.

In San Diego County, hospitals reported an increase in the number of people seeking emergency treatment for heat-related problems.

Sizzling temperatures have caused minor damage to the county’s agriculture industry, but officials fear greater crop losses if there is no break.

San Diego area smog remained at unhealthy levels Wednesday and is expected to be the same today.

For the first time in the four-day heat wave, a power outage occurred locally as residents continued to rely heavily on air conditioners. A Rancho Bernardo power substation shut down at 4 p.m. to prevent an overload, leaving 10,000 customers without electricity for 45 minutes.

Also, 200 homes in southeast Alpine were without electricity overnight after a brush fire destroyed two power poles and wires at 2:40 p.m. Power was to be restored this morning.

Temperatures are expected to drop slightly today and Friday to the mid- to high 80s at the beaches and along the coast as the high-pressure system responsible for the heat wave moves away from Southern California, according to the National Weather Service.

But the respite won’t reach the hot inland areas for a few days, as desert temperatures are forecast to stay between 112 and 120 degrees, National Weather Service forecaster Ray Robben said.

According to meteorologists, the far-reaching heat wave is the product of a massive high-pressure system stationed over the Southwest like a lid on a vast Dutch oven, baking the entire landscape. The lid presses down in a process called “subsidence,” compressing and heating the air beneath it.

In San Diego, a record high temperature of 91 degrees at Lindbergh Field was set at 1:15 p.m., breaking the record of 90 degrees for that date, set in 1976. Normal temperature downtown at this time of year is 73.

Throughout the county, temperatures exceeded the century mark. It reached 119 in Borrego Springs; 108 in Santee and Fallbrook; 106 in El Cajon; 104 in Poway, Lemon Grove and Campo; 103 in Escondido and La Mesa, and 98 in National City.

In Los Angeles, the thermometer reached 109 degrees at the Civic Center, breaking a 14-year-old record for the date by 7 degrees and falling just 3 degrees short of the all-time record for any date, set on Tuesday.

Meanwhile, brush fires continued to plague the Southland.

In San Diego County, two wildfires charred a little more than 1,000 acres and caused $1-million damage to a two-story house on Alpine Boulevard near Interstate 8 and destroyed another home in Pine Hills, near Julian.

For several hours, one of the blazes, centered near Dehesa Road, threatened several million-dollar homes in the Palo Verde area. At its height, flames came within 75 feet of the expensive homes, but were stopped by fire breaks made on the canyon-side by bulldozers operated by the California Department of Forestry.

The fire breaks were just one weapon employed by firefighters, who also used aerial tankers and fire engines. At one point in the afternoon, firefighters were forced to battle more than one blaze, causing aerial tankers to be diverted.

The Dehesa Road fire broke out at 10:15 a.m. in the Alpine Heights area and blackened an estimated 1,200 acres, bringing down power and telephone lines.

By late Wednesday, the fire was 90% contained and was expected to be subdued by late today, CDF spokesman Robert Paul said. An unidentified firefighter was taken to Grossmont Hospital in La Mesa with heat exhaustion, Paul said.

A fire on the Rincon Indian Reservation that started Tuesday night burned about 350 acres before it was contained Wednesday, Paul said. It caused no injuries or damage to structures, he said. A 175-acre blaze in the Agua Tibia wilderness area, at the base of Palomar Mountain, was 75% contained by late Wednesday, Paul said. No injuries had been reported from the fire and it had threatened no buildings, he said.

Since Tuesday, 11 brush fires have been reported in the county, though none have caused serious injuries. Several, however, have destroyed and damaged homes and structures.

Burning permits were suspended by Chief Barritt Neal of the San Diego ranger unit for state forests and campgrounds in San Diego and Imperial counties Wednesday. Established campfire facilities were exempt from the suspension.

In San Diego, water usage was up at the city Water Utilities Department and the County Water Authority, which are trying to get customers to use 10% less water this summer. The authority, which supplies water to most of the county, has seen demand jump 19% in the past week, pushing its drinking water system to capacity Wednesday, said authority spokesman Mark Sadler.

The city’s water-use reduction rate has dropped from 17.8% Friday to 2.9% Wednesday, said department spokesman Kurt Kidman.

San Diego’s power usage soared to an all-time record of 3,000 megawatts at 3 p.m., shattering Tuesday’s record of 2,871 megawatts, said Fred Vaughn, a spokesman for San Diego Gas & Electric. Power consumption in Los Angeles also broke records.

An agricultural heat advisory for coastal and inland areas probably will remain in effect through the weekend. The heat has ruined a small percentage of the berry and other crops. However, the greatest threat is to row crops and the county’s $400-million nursery industry, said Bill Snodgrass, the county’s assistant agricultural commissioner. Uncut flowers are the most susceptible to heat damage.

Tomato, squash, cucumber and other row crop seedlings recently planted--about 25% of the total crop--could be damaged by the heat, he added.

Pollution exceeded the federal standard for unhealthy air Wednesday in El Cajon, Alpine, Kearny Mesa and Escondido. Unfavorable smog conditions are predicted for today.

Crowds continued to swarm to area beaches, keeping lifeguards busy. About 70,000 people have fled to city beaches each day during the heat wave, said David Mico, a San Diego lifeguard.

Many of the beach-goers are out-of-town visitors unaccustomed to Pacific rip currents, which have been unusually strong in recent days because of a northwest ocean swell, Mico said.

Lifeguards, using rescue buoys to pull people ashore, have rescued more than 500 people in the past five days, Mico said. No recent drownings have been reported.

At the San Diego Wild Animal Park, where the temperature has been near 110 degrees this week, animals are getting special care to avoid heat stress. The animals are being kept cool with sprinklers, misters, wading pools and extra showers from hoses, said park spokesman Jeff Jouett. Keepers are keeping a close eye on the biggest animals, such as elephants, which are more susceptible to the heat, he said.

Contributing to this story were Times staff writers Dan Parks and Bonna de la Cruz.