Worst air pollution Hearst, today and tomorrow

Today (16 July): Air quality in Hearst is fair. O3 is fair; AQI and NO2 are medium; PM2.5, PM10, SO2, CO, HCHO, and PM1 are good. Pollution peaks around 1:00 AM (NO2: 59.7/100).
Tomorrow (17 July 2026): Air quality in Hearst is poor. AQI worsens to poor; PM2.5 increases to fair; NO2 increases to poor; PM1 increases to fair; all other pollutants stay as today. Pollution peaks around 7:00 PM (NO2: 67.9/100). 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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Hearst's air quality reflects its forestry and lumber-mill industry in remote northern Ontario, with mill operations contributing modest local emissions amid otherwise clean, sparsely populated boreal surroundings.

Today - 16 July | Pollution peaks at 01:00

AQI:

Medium

59.7/100

PM2.5 (fine particles):

Good

19.1/100

PM10 (coarse particles):

Good

6.9/100

NO2 (nitrogen dioxide):

Medium

59.7/100

O3 (ozone):

Fair

28.8/100

SO2 (sulfur dioxide):

Good

17.3/100

CO (carbon monoxide):

Good

0.0/100

HCHO (formaldehyde):

Good

3.8/100

PM1 (ultrafine particles):

Good

15.7/100

Levels show the poorest local air quality during the day

Tomorrow - 17 July | Pollution peaks at 19:00

AQI:

Poor

67.9/100

PM2.5 (fine particles):

Fair

26.0/100

PM10 (coarse particles):

Good

9.5/100

NO2 (nitrogen dioxide):

Poor

67.9/100

O3 (ozone):

Fair

22.7/100

SO2 (sulfur dioxide):

Good

16.5/100

CO (carbon monoxide):

Good

0.0/100

HCHO (formaldehyde):

Good

1.6/100

PM1 (ultrafine particles):

Fair

21.7/100

Pollen forecast in Hearst

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Frequently Asked Questions

Is air quality bad in Hearst right now?

On 16 July 2026, overall air quality in Hearst is fair. O3 is the main pollutant at 28.8/100. Pollution peaks around 1:00 AM (NO2: 59.7/100).

Will air quality be worse tomorrow in Hearst?

On 17 July 2026, air quality conditions in Hearst will be worse than today, with AQI forecast at poor at 67.9/100. Pollution peaks around 7:00 PM (NO2: 67.9/100).

When is air pollution at its worst in Hearst?

Seasonal air quality in Hearst is closely linked to sawmills and forestry operations near the Quebec border. 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 Hearst 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.

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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