Worst air pollution South End - Boston, today and tomorrow

Today (18 July): Air quality in South End is medium. AQI and O3 are medium; PM2.5, PM10, NO2, SO2, CO, HCHO, and PM1 are good. Pollution peaks around 1:00 PM (O3: 56.1/100).
Tomorrow (19 July 2026): Air quality in South End is medium. All pollutants stay as today. Pollution peaks around 1:00 PM (O3: 59.4/100). 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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Boston's South End sees moderate urban air quality shaped by its central location and arterial traffic on Washington Street and Massachusetts Avenue. The neighbourhood's historic street pattern limits dispersal, though the Southwest Corridor park provides a modest linear green buffer through this densely populated inner district.

Today - 18 July | Pollution peaks at 13:00

AQI:

Medium

56.1/100

PM2.5 (fine particles):

Good

14.8/100

PM10 (coarse particles):

Good

7.1/100

NO2 (nitrogen dioxide):

Good

8.8/100

O3 (ozone):

Medium

56.1/100

SO2 (sulfur dioxide):

Good

1.7/100

CO (carbon monoxide):

Good

0.0/100

HCHO (formaldehyde):

Good

6.6/100

PM1 (ultrafine particles):

Good

16.2/100

Levels show the poorest local air quality during the day

Tomorrow - 19 July | Pollution peaks at 13:00

AQI:

Medium

59.4/100

PM2.5 (fine particles):

Good

13.2/100

PM10 (coarse particles):

Good

9.1/100

NO2 (nitrogen dioxide):

Good

12.2/100

O3 (ozone):

Medium

59.4/100

SO2 (sulfur dioxide):

Good

1.4/100

CO (carbon monoxide):

Good

0.0/100

HCHO (formaldehyde):

Good

7.7/100

PM1 (ultrafine particles):

Good

15.5/100

Other Landmarks in Boston

Sports venues in Boston

Frequently Asked Questions

Is air quality bad in South End right now?

On 18 July 2026, overall air quality in South End is medium. AQI is the main air quality indicator at 56.1/100. Pollution peaks around 1:00 PM (O3: 56.1/100).

Will air quality be worse tomorrow in South End?

On 19 July 2026, air quality conditions in South End will be similar to today, with AQI forecast at medium at 59.4/100. Pollution peaks around 1:00 PM (O3: 59.4/100).

When is air pollution at its worst in South End?

South End's air quality follows a clear seasonal pattern — the cleanest conditions typically arrive with the more unsettled weather of spring and autumn, whereas summer heat waves, often worsened by haze drifting in from other regions, bring the year's worst air. Coastal sea breezes can offer some relief from inland summer ozone buildup.

Are air quality levels in South End 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: 18 July 2026 at 21:30 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