ST. PAUL, Minn. — The quality of air in St. Paul reached 256 on the 500-point federal index – momentarily the worst in the country. To blame: Smoke from massive eastern Canada wildfires. The pollution was worse earlier in the week in northeast states but has drifted west. Nick Witcraft, a state meteorologist, said the 256 St. Paul reading, at 6 p.m., was the worst in Twin Cities history. The city was in the AQI red zone. That, said Witcraft, was unhealthy for everyone but particularly dangerous for children, older people, and those with asthma and conditions like diabetes and heart disease. Earlier this spring there was pollution in southern Minnesota and western Wisconsin from a separate spate of massive wildfires in northern parts Manitoba and Alberta .
Earlier: Canada wildfire smoke keeps blowing south
Mid-day readings. The state Pollution Control Agency monitors fast-changing shifts in ozone and smoke particulate contaminants. This at 2 p.m.
Air quality index
> Good: 0-50.
> Moderate: 51-100.
> Unhealthy for vulnerable people: 101-150.
> Unhealthy for everyne: 151-200.
> Very unhealthy: 201-300.
> Hazardous: 301-500.