Hot weather and wildfires continue to diminish the Treasure Valley’s air quality.

The Idaho Department of Environmental Quality posted a yellow air quality alert for Thursday for Ada and Canyon counties.

This is the fourth consecutive yellow air quality alert this week.

The forecast Air Quality Index (AQI) for Thursday is 90 for ozone and particles. Under a yellow, or moderate, alert, the air quality is acceptable; however, people who are unusually sensitive to ozone may have respiratory symptoms.

An index above 100 warrants an orange alert, which means the air is unhealthy for people with lung and breathing problems or other sensitivities.

Under a yellow alert:

• Open outdoor burning is prohibited in Ada County by municipal and county ordinance when the AQI is 60 or greater.

• Open outdoor burning is prohibited in the incorporated cities within Canyon County when the AQI is 60 or greater.

• Open outdoor burning is prohibited in unincorporated Canyon County when the AQI is 75 or greater.

• All individuals may want to consider postponing strenuous activities until air quality improves.