A temperature inversion where warm air settles over cool air has caused a hazy fog to settle over Edmonton. The inversion traps low-level pollutants causing poor air quality and health concerns, air travel delays and poor visibility for vehicles. Children, seniors and pregnant women, people with heart, lung issues and diabetes, homeless Edmontonians, and outdoor workers should be extra careful during this time. Environment Canada forecasts that air quaility should improve by the weekend.