Weather Is a Turnoff, So Many Turn On Coolers : Heat: Temperatures generate a big demand for air conditioning and electricity. It’s summer’s last hurrah, forecasters say, even though it ended Monday.

Orange County residents Tuesday tried to beat the heat wave--and its accompanying smog--which lingered over the Southland for a second straight day by turning on air-conditioning units in record numbers, officials said.

The heat wave, generated when the stubborn low-pressure system that soured the summer moved eastward, was expected to dissipate noticeably by the weekend, said meteorologist Steve Burback of WeatherData, which provides forecasts for the Times.

“It’ll start cooling off some,” Burback said.

Southern California Edison spokesman Steve Hansen said electricity usage throughout the Southland was the highest since summer began, forcing workers at the utility’s Huntington Beach plant to turn on its fourth generator for the first time in eight months.

By 3:30 p.m., electricity usage exceeded 16,500 megawatts, topping the summer season high of 15,868 megawatts, set Aug. 23.

The heat wave--which spilled over into autumn when that season began Monday--was felt strongest in Anaheim, where the high temperature for Tuesday reached 98, Burback said. In other parts of the county, Santa Ana recorded a high temperature of 96, El Toro thermometers topped out at 95 and it was 91 in San Juan Capistrano.

Beach communities were spared the sizzling heat experienced in inland cities. The high temperature for Newport Beach was 75, and the high in Huntington Beach was 76.

High temperatures for the weekend, however, were expected to drop into the mid-60s for the beach areas and the low 80s for the inland areas.

Tuesday’s heat wave also brought with it high levels of smog, said Paula Levy of the South Coast Air Quality Management District.

For several minutes in the afternoon, El Toro surpassed a smog level that, if sustained for an hour or more, would have triggered a first-stage smog alert. A health advisory for the Saddleback Valley area remained in effect until sundown, she said.

The heat and relatively high humidity made work uncomfortable for residents who labored all day without air conditioning in businesses and schools.

Newport Beach resident John Eaglebert, 39, spent the morning in a Los Angeles print shop, where the thermometer registered a whopping 120. The heat was so unbearable, he said, that by 2 p.m., he headed home.

Once there, he shucked his shirt and shoes, and he and his neighbor, Diane Farmer, climbed atop his mobile home to spend a lazy afternoon sipping beers and watching the cars chug past on the Coast Highway below.

“This is the coolest place in town,” boasted Farmer, 32. “You can’t get better than this.”

Some of those lucky enough to have air conditioners were disappointed to switch them on, sometimes for the first time this year, only to find they did not work.

“It was unbearable,” lamented Holly Hayden, 35, of Lemon Heights, who was forced to call an air-conditioning repairman to make a house call. “It just blew hot air. This summer has been so cool, I haven’t needed to turn it on at all.”

Isabel Hellman, who owns a Santa Ana air-conditioning repair shop, said she has been swamped with calls for service.

“We didn’t have a summer at all as far as business goes,” she said.

Edison’s Hansen suggested that residents conserve electricity to avoid brownouts, which occur when the utility is unable to supply the demand of electricity.

He suggested that people keep curtains and blinds closed during the hottest time of day and shut fireplace dampers.

“There’s a lot of things you can do,” he said, “without major expense.”