Worst air pollution Trail Ridge Road - Granby, today and tomorrow

Today (20 September): Air quality in Trail Ridge Road is moderate. AQI and O3 are moderate; NO2 is fair; PM2.5, PM10, SO2, CO, HCHO, and PM1 are good. Pollution peaks around 4:00 AM (O3: 58.9/100).
Tomorrow (21 September 2026): Air quality in Trail Ridge Road is poor. AQI worsens to poor; NO2 increases to moderate; O3 increases to poor; all other pollutants stay as today. Pollution peaks around 4:00 AM (O3: 61.5/100). Airmine updates local air quality forecasts four times daily.

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

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In Trail Ridge Road, with fewer vehicles on the road, nearby cropland dust and periodic burning outweigh traffic as a pollution source. Tree cover nearby helps soften the local particulate load to a degree. Actual air quality on a given day still depends heavily on local wind and weather conditions.

Today - 20 September | Pollution peaks at 04:00

AQI:

Moderate

58.9/100

PM2.5 (fine particles):

Good

19.8/100

PM10 (coarse particles):

Good

8.0/100

NO2 (nitrogen dioxide):

Fair

34.8/100

O3 (ozone):

Moderate

58.9/100

SO2 (sulfur dioxide):

Good

0.7/100

CO (carbon monoxide):

Good

0.5/100

HCHO (formaldehyde):

Good

2.9/100

PM1 (ultrafine particles):

Good

3.0/100

Levels show the poorest local air quality during the day

Tomorrow - 21 September | Pollution peaks at 04:00

AQI:

Poor

61.5/100

PM2.5 (fine particles):

Good

19.1/100

PM10 (coarse particles):

Good

6.6/100

NO2 (nitrogen dioxide):

Moderate

48.5/100

O3 (ozone):

Poor

61.5/100

SO2 (sulfur dioxide):

Good

1.2/100

CO (carbon monoxide):

Good

0.6/100

HCHO (formaldehyde):

Good

4.2/100

PM1 (ultrafine particles):

Good

2.7/100

Other Landmarks in Granby

Frequently Asked Questions

Is air quality bad in Trail Ridge Road right now?

On 20 September 2026, overall air quality in Trail Ridge Road is moderate. AQI is the main air quality indicator at 58.9/100. Pollution peaks around 4:00 AM (O3: 58.9/100).

Will air quality be worse tomorrow in Trail Ridge Road?

On 21 September 2026, air quality conditions in Trail Ridge Road will be worse than today, with AQI forecast at poor at 61.5/100. Pollution peaks around 4:00 AM (O3: 61.5/100).

When is air pollution at its worst in Trail Ridge Road?

February through April tends to be calm here, with wind speeds averaging around 15 km/h and temperatures near -4°C -- conditions cool and still enough for particulate matter and smoke to settle near the ground instead of dispersing. From June to August, temperatures average around 16°C, warm enough for strong sun and heat to drive ground-level ozone formation.

Are air quality levels in Trail Ridge Road 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.

Why doesn’t the forecast always reflect wildfire impacts?

Airmine’s forecast uses CAMS (Copernicus Atmosphere Monitoring Service) as its background atmospheric model. While CAMS includes wildfire emissions, these are derived from satellite observations and are not available in real time. During rapidly evolving wildfire events, there may therefore be a delay before increased emissions are incorporated into the model. As a result, the forecast may temporarily underestimate PM₂.₅ and other pollutants associated with wildfire smoke.

During rapidly evolving wildfire events, CAMS may lag by approximately 1–2 days before increased wildfire emissions are fully represented, which can lead to temporary underestimation of PM₂.₅ concentrations in Airmine’s forecast.

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Data provided by Airmine — Last update: 20 September 2026 at 14:33 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.

Disclaimer: Forecasts are provided for informational purposes only and should not be relied upon as medical advice. Actual pollen and air quality conditions may vary from the forecast. If you have allergies, asthma, or another medical condition, consult a healthcare professional. Please see our Terms of Service for important information about limitations of liability.

Some text on this page may be generated or summarised using artificial intelligence (AI). Wherever possible, AI-generated content is enriched with Airmine's proprietary data to improve its accuracy and relevance. However, AI-generated content may still contain errors, omissions, or inaccuracies.

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