Worst air pollution Marathon, today and tomorrow

Today (16 July): Air quality in Marathon is medium. AQI, NO2, and O3 are medium; PM2.5, PM10, SO2, CO, HCHO, and PM1 are good. Pollution peaks around 8:00 AM (O3: 49.1/100).
Tomorrow (17 July 2026): Air quality in Marathon is fair. O3 increases to fair; PM1 increases to fair; all other pollutants stay as today. Pollution peaks around 11:00 PM (NO2: 57.4/100). Airmine updates local air quality forecasts four times daily.

For long term forecasts and maps, see the Airmine app

Developed with support from the European Space Agency (ESA)’s Business Applications and Space Solutions (BASS) team

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Marathon's air quality benefits from its remote Lake Superior shoreline position, with lake breezes providing reliable ventilation amid otherwise clean, sparsely populated boreal surroundings and legacy mining activity.

Today - 16 July | Pollution peaks at 08:00

AQI:

Medium

49.1/100

PM2.5 (fine particles):

Good

16.9/100

PM10 (coarse particles):

Good

5.7/100

NO2 (nitrogen dioxide):

Medium

42.8/100

O3 (ozone):

Medium

49.1/100

SO2 (sulfur dioxide):

Good

9.1/100

CO (carbon monoxide):

Good

0.0/100

HCHO (formaldehyde):

Good

6.8/100

PM1 (ultrafine particles):

Good

19.7/100

Levels show the poorest local air quality during the day

Tomorrow - 17 July | Pollution peaks at 23:00

AQI:

Medium

57.4/100

PM2.5 (fine particles):

Good

19.4/100

PM10 (coarse particles):

Good

6.1/100

NO2 (nitrogen dioxide):

Medium

57.4/100

O3 (ozone):

Fair

35.0/100

SO2 (sulfur dioxide):

Good

10.4/100

CO (carbon monoxide):

Good

0.0/100

HCHO (formaldehyde):

Good

3.2/100

PM1 (ultrafine particles):

Fair

20.5/100

Pollen forecast in Marathon

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Frequently Asked Questions

Is air quality bad in Marathon right now?

On 16 July 2026, overall air quality in Marathon is medium. AQI is the main air quality indicator at 49.1/100. Pollution peaks around 8:00 AM (O3: 49.1/100).

Will air quality be worse tomorrow in Marathon?

On 17 July 2026, air quality conditions in Marathon will be worse than today, with O3 forecast at fair at 35.0/100. Pollution peaks around 11:00 PM (NO2: 57.4/100).

When is air pollution at its worst in Marathon?

The air over Marathon varies through the year, influenced by its pulp mill on the shore of Lake Superior. Air quality is generally very good outside of wildfire season, though hot, dry summers can bring smoky, hazy stretches when fires burn across the wider region. Because the population is small, local emissions rarely matter as much as what drifts in from distant fires.

Are air quality levels in Marathon based on measurements or forecasts?

It is forecasts derived by downscaling forecasts provided by EU’s Copernicus Atmosphere Monitoring Service (CAMS) by taking into account local conditions such as traffic patterns. CAMS bases its forecast on satellite measurements of particles and chemical compounds in the atmosphere. Airmine’s services were developed with support from the European Space Agency (ESA)’s Business Applications and Space Solutions (BASS) team.

Check air quality in other popular cities:

Data provided by Airmine — Last update: 16 July 2026 at 10:33 CEST (Data is updated four times daily.)

This forecast is produced independently using Airmine's own atmospheric data and models.

Unless explicitly made clear, the content on this site has not been paid for by external organisations and is Airmine's sole responsibility.

For long term forecasts and maps, see the Airmine app