Clearly Hot

Triple-digit heat returned to the San Fernando Valley this week, but with August drawing to a close Southern California still hasn’t suffered a major smog alert.

“We have another 40 days in smog season,” said Bill Kelly, a spokesman for the South Coast Air Quality Management District. “But at this point this is the longest time we’ve gone without a Stage 1 episode. It’s looking to be another record clean year.”

In the San Fernando Valley on Tuesday, Burbank reported a high of 96 degrees while Chatsworth hit 103, Woodland Hills 104 and Van Nuys 102 degrees, according to the National Weather Service.

Kelly said cooler-than-normal temperatures for most of this summer helped dissipate stagnant air masses, which usually bring hotter weather and allow pollution to build.

Another factor, he said, are pollution control programs and stricter emission standards that bring down dangerous levels of pollutants that cause smog.

AQMD statistics show that so far this year there have been no Stage 1 episodes--defined as .20 parts ozone per million parts of air. Last year, there were 12 Stage 1 episodes due to more stagnant conditions.

“As temperatures heat up to more seasonable levels in late August and early September, we may see higher smog levels,” Kelly said.

Meteorologist Stacey Johnstone of WeatherData Inc., which provides weather information for The Times, said that for the most part marine air has kept temperatures lower than normal.

Generally, high pressure sits over the area keeping temperatures for late summer in the 90s and low 100s.