We haven't had air this bad in the Twin Cities since 2005. That's the last time the Minnesota Pollution Control Agency had to issue a red alert for air quality due to what's called winter stagnation, which traps all of the fine particulates emitted in cities down at the surface.
That alert means the air is unhealthy for everyone, not just sensitive groups, according to MPCA Research Meteorologist Matt Taraldsen.
“A lot of times the first symptoms that you’re being impacted by air quality, you know, you can feel it in your chest, you kind of have shortness of breath, you start coughing, you have a tickle in your throat,” Taraldsen explains. “Listen to your body. Those are good indications your body is telling you to go inside.”
The red alert covers much of the immediate Twin Cities metro, along with the Fargo-Moorhead area. Most of the rest of the central part of the state remains under an orange alert where sensitive groups should avoid prolonged exertion outside.
“Been a long while and even these hourly observations that we've already seen in places like Apple Valley and Lakeville are something we haven't seen for about 15 years,” Taraldsen explains.
Taraldsen says conditions will improve when a cold front moves through the state Wednesday afternoon.
“So this is what we call winter stagnation, which is basically just light winds, not just at the surface, but all the way up in the atmosphere,” says Taraldsen. “And the light winds and the temperature profile kind of keeps all of the pollution that's emitted in cities right down at the surface.”
The alert for Minnesota is in effect until 6:00 p.m. Wednesday.