Worst air pollution Center City - Philadelphia, today and tomorrow
Today (20 September): Air quality in Center City is fair. AQI, PM2.5, NO2, O3, and PM1 are fair; PM10, SO2, CO, and HCHO are good. Pollution peaks around 7:00 AM (PM1: 34.3/100).
Tomorrow (21 September 2026): Air quality in Center City is fair. PM2.5 decreases to good; PM1 decreases to good; all other pollutants stay as today. Pollution peaks around 3:00 PM (NO2: 34.2/100). 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 Center City, congested streets and dense urban activity keep particulate matter and nitrogen dioxide readings consistently on the higher side. Tree cover in the area softens the impact somewhat, catching particulates before they disperse further. Nearby areas with a similar setup tend to show a comparable air quality baseline.
Today - 20 September | Pollution peaks at 07:00
AQI:
Fair
34.3/100
PM2.5 (fine particles):
Fair
25.5/100
PM10 (coarse particles):
Good
16.5/100
NO2 (nitrogen dioxide):
Fair
32.5/100
O3 (ozone):
Fair
22.7/100
SO2 (sulfur dioxide):
Good
1.1/100
CO (carbon monoxide):
Good
0.6/100
HCHO (formaldehyde):
Good
2.7/100
PM1 (ultrafine particles):
Fair
34.3/100
Levels show the poorest local air quality during the day
Tomorrow - 21 September | Pollution peaks at 15:00
AQI:
Fair
34.2/100
PM2.5 (fine particles):
Good
16.8/100
PM10 (coarse particles):
Good
12.6/100
NO2 (nitrogen dioxide):
Fair
34.2/100
O3 (ozone):
Fair
28.8/100
SO2 (sulfur dioxide):
Good
2.1/100
CO (carbon monoxide):
Good
0.6/100
HCHO (formaldehyde):
Good
3.8/100
PM1 (ultrafine particles):
Good
17.2/100
Other Landmarks in Philadelphia
Sports venues in Philadelphia
Frequently Asked Questions
Is air quality bad in Center City right now?
On 20 September 2026, overall air quality in Center City is fair. AQI is the main air quality indicator at 34.3/100. Pollution peaks around 7:00 AM (PM1: 34.3/100).
Will air quality be worse tomorrow in Center City?
On 21 September 2026, air quality conditions in Center City will be similar to today, with AQI forecast at fair at 34.2/100. Pollution peaks around 3:00 PM (NO2: 34.2/100).
When is air pollution at its worst in Center City?
Particulate levels here tend to peak during the winter months more than any other season, as reduced winter air mixing lets traffic and heating emissions accumulate close to the ground. Warmer months bring a different problem here: ground-level ozone, which forms readily from traffic emissions baking in strong sunlight, and can spike further during wildfire smoke events.
Are air quality levels in Center City 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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