Worst air pollution Bethlehem, today and tomorrow

Today (9 August): Air quality in Bethlehem is fair. AQI, NO2, O3, and PM1 are fair; PM2.5, PM10, SO2, CO, and HCHO are good. Pollution peaks around 11:00 AM (O3: 38.1/100).
Tomorrow (10 August 2026): Air quality in Bethlehem is fair. PM2.5 increases to fair; all other pollutants stay as today. Pollution peaks around 11:00 AM (O3: 36.1/100). 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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Bethlehem's air quality in Pennsylvania reflects the Lehigh Valley's position in the mid-Atlantic corridor, with vehicle emissions from US-22 and the former Bethlehem Steel complex legacy contributing local sources. The surrounding Pennsylvania ridgelines provide partial topographic barriers, while the Lehigh river valley provides some natural ventilation and the broader mid-Atlantic regional airshed contributes upwind industrial and urban sources from the Philadelphia and New York corridors throughout the year.

Today - 9 August | Pollution peaks at 11:00

AQI:

Fair

38.1/100

PM2.5 (fine particles):

Good

17.9/100

PM10 (coarse particles):

Good

5.0/100

NO2 (nitrogen dioxide):

Fair

22.3/100

O3 (ozone):

Fair

38.1/100

SO2 (sulfur dioxide):

Good

2.4/100

CO (carbon monoxide):

Good

0.0/100

HCHO (formaldehyde):

Good

5.9/100

PM1 (ultrafine particles):

Fair

22.8/100

Levels show the poorest local air quality during the day

Tomorrow - 10 August | Pollution peaks at 11:00

AQI:

Fair

36.1/100

PM2.5 (fine particles):

Fair

22.9/100

PM10 (coarse particles):

Good

8.0/100

NO2 (nitrogen dioxide):

Fair

24.3/100

O3 (ozone):

Fair

36.1/100

SO2 (sulfur dioxide):

Good

2.2/100

CO (carbon monoxide):

Good

0.0/100

HCHO (formaldehyde):

Good

6.3/100

PM1 (ultrafine particles):

Fair

27.1/100

Pollen forecast in Bethlehem

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Air quality forecasts for neighbourhoods and landmarks in Bethlehem

Frequently Asked Questions

Is air quality bad in Bethlehem right now?

On 9 August 2026, overall air quality in Bethlehem is fair. AQI is the main air quality indicator at 38.1/100. Pollution peaks around 11:00 AM (O3: 38.1/100).

Will air quality be worse tomorrow in Bethlehem?

On 10 August 2026, air quality conditions in Bethlehem will be similar to today, with AQI forecast at fair at 36.1/100. Pollution peaks around 11:00 AM (O3: 36.1/100).

When is air pollution at its worst in Bethlehem?

Bethlehem's air quality follows a clear seasonal pattern: the calmest air of the year usually arrives well after the summer ozone season fades, but extended summer heat waves, often worsened by regional haze, bring the toughest air quality stretch. Dense urban traffic corridors add a persistent background level of pollution that varies less by season than ozone does.

Are air quality levels in Bethlehem 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: 9 August 2026 at 20:27 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.

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