Sneak Preview of Summer: Smog, Highs in 90s

Summer is officially two weeks away, but Southern California got a preview Thursday as a strong high-pressure system settled in to push temperatures into the 90s, foul the air and promise more of the same for the weekend.

The Los Angeles Civic Center mercury climbed to 95, up a dozen degrees from the day before. It was 102 in Monrovia; 106 in Palm Springs; 98 in Pasadena, Montebello and San Gabriel; 102 in Riverside and San Bernardino, and 112 in Blythe. The latter shared honors with Gila Bend and Coolidge, Ariz., as the hottest spots in the nation.

Today should be a repeat, the National Weather Service said.

Temperatures are expected to be in the 100s in the inland valleys and deserts.

Coastal areas should be warm and clear through the weekend but with some fog locally along the coast as marine air sneaks in along the edges. There were cooler temperatures and fog along some beaches on Thursday morning. In San Diego, dense fog made driving hazardous, especially in the inland mesa areas.

Mountain resorts will have highs in the 70s and 80s. Upper Southern California deserts will have highs of 94 to 104, while the lower-desert highs will range from 106 to 112.

Smog levels were high Thursday as the high-pressure system produced a strong temperature inversion. The South Coast Air Quality Management District declared first-stage alerts in numerous sectors, including metropolitan Los Angeles, South-Central Los Angeles, Whittier and parts of the San Gabriel Valley, the San Fernando Valley and the Corona-Norco area.

A first-stage alert, meaning the air is unhealthful for everyone, is declared when the Pollutants Standards Index registers from 200 to 275.

Thursday’ overnight low in downtown Los Angeles was 67 degrees. The high relative humidity was 70%, and the low was 26%.

The onset of hot weather already has this looking like an unusual June. Normally, midday temperatures for the month are mostly in the 70s near the coast and in the 80s around the foothills. However, there have been some Junes in which 100-degree readings have been recorded.