Prompts winter weather advisories as cold air moves in Friday night

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You’ve probably seen that the Minnesota Pollution Control Agency has 

 over parts of Minnesota this week to the red category.

But what’s the deal with that donut hole in the air quality alert over the Twin Cities? 

It’s sometimes called the ozone paradox. It turns out that ozone concentrations can be higher around cities and even in rural areas than in the inner urban core. The complex chemistry of ozone formation can actually work to reduce ozone in inner cities closer to the pollution sources. 

Basically, the same nitrous oxides (NOx) and volatile organic compounds (VOC) that cause ozone to form in cities can also degrade the newly created ozone as time goes by. 

 in cities and surrounding areas from the Belgian Interregional Environment Agency.

Why are ozone concentrations higher in rural areas than in cities?

The last time the Minnesota Pollution Control Agency recorded a red (unhealthy for all) level of ozone in Minnesota was in June of 2012. Air quality readings for ozone are as high as 172 in St. Michael Tuesday afternoon. 

Here’s the updated text from the MPCA’s latest air quality alert upgrade. 

And finally, here’s the latest forecast discussion form the MPCA meteorologists. 

Weather and Climate News

Updraft® - Minnesota Weather News

Paul Huttner

Author

Highest ozone readings in 11 years for Minnesota. 

So what's up with the donut hole in the air quality alert over the Twin Cities?

Go Deeper.

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