Monday, June 26, 2017 Last Update: 8:26 AM

Heat wave means unhealthy air this weekend across parts of Southern California

89.3 KPCC
Sunday, June 18, 2017 - 11:50

In Southern California, pollutants get trapped inland against the San Gabriel and San Bernardino mountains, making ozone levels higher in Riverside and San Bernardino counties than almost anywhere else. Ozone levels typically peak around 2 p.m. in downtown ...