(Portland, OR) -- An air pollution advisory has been issued for the Portland-Vancouver area through Tuesday night. Hot temperatures and a lack of winds are allowing ozone to build up in the atmosphere. The air quality is unhealthy for sensitive groups. They should limit their time outside. You can help reduce the pollution by limiting driving, don't use gas powered landscaping equipment, and don't use aerosol sprays. Refilling your vehicle in the morning or evening, when it's cooler, also helps reduce pollution.