Summer Waits Till Autumn to Unleash First Heat Wave

A weak Santa Ana condition Tuesday produced the first significant heat wave in months, fueling a grass fire in North San Diego County, prompting the county Air Pollution Control District to issue a health advisory and aggravating San Diegans who had grown accustomed to unseasonably cool temperatures in recent months.

The searing heat was replicated throughout Southern California, breaking an 85-year-old record in Los Angeles.

The mercury climbed to 87 degrees at Lindbergh Field shortly before noon, 6 degrees shy of San Diego’s Oct. 1 record set in 1965, said Wilbur Shigehara, senior meteorologist for the National Weather Service. Humidity dropped to 37%, signaling the dry conditions of a Santa Ana, he said.

“I don’t know if we have the Santa Ana to thank or to blame for this heat wave,” Shigehara said, adding that the temperatures countywide were about 10 degrees above normal for this time of year. “But there is nothing outrageous about this heat wave; it looks very typical for San Diego.”

Hotter spots in the county included 108 at Gillespie Field in El Cajon; 104 in Fallbrook; 103 in Poway, Santee and Spring Valley; 101 in Alpine and Escondido; 100 in La Mesa and Ramona, and 94 in Campo. Only slightly cooler were Coronado with 92, Julian with 90, Imperial Beach with 86, Del Mar with 83 and Mt. Laguna with 78.

The thermometer in downtown Los Angeles soared to 100 degrees Tuesday, breaking the record of 99 set in 1906. Hotter still were Burbank, where it reached 101, and Fillmore in Ventura County, which it was 102.

The high in Van Nuys was 105, 100 in Long Beach and Northridge, 108 in Monrovia, 102 in Montebello and 104 in Pasadena.

The weak Santa Ana originated in Nevada and is expected to peak by today or Thursday, Shigehara said. He said it was ironic that the summer was one of the coolest on record, yielding only a handful of normal or above-normal days, but that since autumn arrived Sept. 21, temperatures have been at or above normal.

Health risks came with the heat. The San Diego County Air Pollution Control District issued a health advisory Tuesday afternoon cautioning residents from the coast to 20 miles inland to curtail vigorous outdoor activity. The warning remained in effect until 7 p.m.

In North County, a 112-acre grass fire forced the closure of California 76 west of Interstate 15, between Via Monserate on the west and Gird Road on the east.

The fire, which started shortly after 1 p.m. and quickly spread along the San Luis Rey River and moved northeasterly along Gird Road between Bonsall and Pala Mesa, was fought by 120 firefighters from the California Department of Forestry and other area agencies, CDF spokeswoman Delores Fremter said.

The fire was contained about 4 p.m. and the road reopened at 6 p.m., CDF officials said.

Their efforts were hampered for a time when they came across five 55-gallon barrels containing unidentified chemicals along the river bottom. A county hazardous-materials emergency response team was sent to the scene and identified the chemicals as nonflammable floor wax.

“We knew of their existence back in June, and we asked the property owner, who was the unlucky recipient of the abandoned barrels, to dispose of them,” said Nick Vent, a hazardous-materials specialist. But since the wax is not considered a hazardous material, the department could not enforce its cleanup, he said.

“But the CDF got a little surprise when they came across them,” he said.

The fire caused no injuries and threatened no homes, Fremter said. Its cause was not known Tuesday.

High temperatures in San Diego County today and Thursday along the coast will be in the upper 80s, with overnight lows in the mid- to upper 60s, Shigehara said. Inland areas can expect daytime highs between 90 and 105 through Thursday, with lows in the upper 50s.

The ocean temperature is 66 degrees. The surf is 3 to 5 feet.

Mountain highs will range from 80 to 90, with lows in the 60s. Desert highs will be between 105 and 112, and lows will range from 65 to 75.

The weekend will remain warm, but the mercury should drop a few degrees, Shigehara said. By early next week, a gradual cooling trend will bring temperatures back to seasonal, and the coastal fog and low clouds will return, he said.

For most Southern Californians, the late-breaking heat wave quickly became a test of stamina and resourcefulness.

Shoppers downtown kept to the shady side of the street, lines of bus riders gathered in any available shade, office workers refused to leave their air-conditioned cubicles. And that was bad news for Thousand Oaks hot dog vendor John Smiley.

“When it gets hot like this, I’ll probably eat more than I sell,” said Smiley, taking off his red golfing cap and wiping his brow. “People don’t even step out of their office.”

Huddled in a tiny patch of shade in the middle of an asphalt parking lot in downtown Los Angeles, attendant Felipe Aguilar contorted his face as he pointed to his enemy--a hardtop sedan, windows rolled up, vinyl upholstery and, ugh, a black steering wheel.

As beads of sweat dripped off his forehead, Aguilar demonstrated his plan of attack, sticking out two fingers as he pretended to barely touch the steering wheel.

“Aieeee!” he yelped, just thinking about getting in the car. “That’s hot.”

At Santa Monica, where the afternoon temperature was a breezy 72 degrees, county lifeguards doubled their usual weekday staff of 15 to brace for the crowds. Lt. Nick Steers said he knew it was going to be hot inland when he awoke to clear skies.

“After 26 years of doing this,” Steers said, “you kind of eyeball it.”

The crowds started showing up around noon--”an extended lunch break,” he said. “We have a lot of people who are ditching their work, even some high school and college kids playing hooky from their appointed duties.”

Despite the fuzzy brown haze that hung over much of the Los Angeles Basin, air quality officials said the heat “literally blew the lid off” the inversion layer that normally makes such days as smoggy as they are sticky.

As long as the air above the inversion layer is warmer than the air below, the smog cannot rise, said Tom Eichhorn, a spokesman for the South Coast Air Quality Management District. But when it gets this hot, the air below breaks through and toxins dissipate into the atmosphere.

Contributing to this report were Times staff writers Tom Gorman, Jesse Katz, Edmund Newton and Psyche Pascual.