FORECAST SUMMARY: Saturday, July 15, 2023, through Sunday, July 16, 2023

OZONE: 8-hour average Ozone concentrations will average mostly Moderate.

PM-2.5: 24-hour average Fine Particulate levels will range from Moderate to Unhealthy for Sensitive Groups (USG).

An Air Quality Action Day Advisory has been issued for Sunday, July 16th, 2023 for PM-2.5.

This is a statewide alert.

FORECAST DISCUSSION:

Smoke forecast models continue to show a large plume originating from wildfires in western and central Canada sinking in from the northwest. Evidence of this is seen by increased PM2.5 readings late Friday and early Saturday to our west across Minnesota and northwest Wisconsin. As the plume continues moving east/southeast, increases in ground level PM2.5 across our state are expected.

This plume will affect the Upper Peninsula first and we have an Air Quality Action Day in place Saturday highlighting the threat for USG PM2.5 concentrations. The threat for USG PM2.5 moves south across the rest of the state Sunday; therefore, we are issuing a statewide Air Quality Action Day for Sunday. While we anticipate daily averages of PM2.5 to stay USG hourly concentrations into the Unhealthy level are possible during this event.

Clouds in the forecast with rain chances should keep ozone in check Saturday and Sunday, but ozone concentrations will be watched along with the PM2.5 trends. Increased PM2.5 is known to enhance ozone production. We are forecasting Moderate ozone both Saturday and Sunday across the state, but if we feel ozone will increase into the USG range, we will update our forecast areas to reflect the change, triggering EnviroFlash notifications.

 EXTENDED FORECAST:

There are signs the smoke plume could clear the region early next week, but lingering fine particulate could increase ozone concentrations. Conditions will be evaluated daily until the threat for increased pollution ends across the state.

Forecast updated by: Stephanie Hengesbach on Saturday, July 15th, 2023

Next Forecast Update: Sunday, July 16th, 2023