L.A. to Get the Third Degree--Again

The fact that California is full of hot air may not come as a surprise to some folks, and this time there’s a meteorological explanation.

Blame this week’s heat wave on a massive dome of air at 18,000 feet that formed at near-freezing temperatures and is steaming up as high pressure forces it to the earth, said Wes Etheredge of WeatherData Inc., which provides weather information for the Times.

Californians are not sweating it out alone.

The dome covers Washington, Oregon and parts of New Mexico, he said, causing a scorcher that will last until Thursday.

“Expect a few temperature records to be broken,” Etheredge said.

High readings in the Los Angeles Basin on Monday soared as high as 107 degrees in Chatsworth, and today should be even hotter, with highs up to 108 forecast for the San Fernando Valley.

By Wednesday, temperatures should start dropping as the high pressure begins to weaken and the dome starts moving east. By Thursday, things should get back to normal as highs reach the upper 60s along the coast to the low 90s in the valleys.

“It’s normal to see periods like this in summer,” said Etheredge. “It’s just a little hot.”

A little may seem like an understatement to residents of the San Fernando Valley, where temperatures have pushed into the 100s since Sunday. Top readings on Monday included 105 in Woodland Hills, Northridge and Van Nuys and 101 in Burbank.

The San Gabriel Valley was almost as hot, with highs of 106 in Monrovia and 102 in Pasadena.

The top reading downtown was 94--hot, but still 6 degrees short of the 100-degree record for the date, set in 1918.

Along the beaches of the Santa Monica Bay, an onshore breeze kept things a lot cooler, with highs of 78 in Venice and 74 in Redondo Beach.

If you weren’t lucky enough to spend Monday sprawled out on the sand, chances are you cranked up the air conditioner in your home and office.

In fact, so many Southland residents used extra electricity during peak heat hours on Monday that Southern California Edison issued an advisory to its 4.3 million customers.

“If just half of our . . . customers would turn off one 100-watt light bulb being needlessly used, it would go a long way in easing any potential power bind,” said John Ballance, Edison’s manager of grid dispatch and operations.

He recommended that customers set their thermostats at 78 degrees, avoid cooling unoccupied rooms and use curtains to block out the sun’s searing rays.

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Heat Watch

The current mini-heat wave will continue today. The near-record highs should subside later this week.

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Location Monday’s high Record for day Burbank 101 101 (1971) Chatsworth 107 107 (1997) Civic Center 94 100 (1918) L.A. Airport 75 n/a Long Beach 95 94 (1997) Pasadena 102 n/a Santa Monica 75 n/a

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Sources: Weather Data, National Weather Service