The downtown Reno, Nevada, skyline is barely visible due to wildfire smoke on Monday, July 30, 2018. According to Washoe County health authorities, several wildfires burning in Nevada and in California have caused air quality to deteriorate in the Reno, Nevada, area over the past week. Health officials in Washoe County Health District's Air Quality Management have reported that Washoe County experienced the highest (worst) level of ozone air pollution since 2008. An Air Quality Index (AQI) for ozone was 140 this past Sunday, Unhealthy for Sensitive Groups. The highest ever for ozone in Washoe County was an AQI of 164 in 1984, Unhealthy.