Tucson is seeing its worst ozone pollution since 2012.
The ozone pollution has exceeded federal standards for ground-level ozone five times this year.
County officials say we're only halfway through the ozone season.
In the past three years, Tucson has had five days when ozone levels exceeded federal standards.
Officials don't know why the levels are so high, but paired with the smoke from all the wildfires, may also lower the air quality over the weekend.