Outdoor
Outdoor activity is generally possible, but conditions are not ideal.
Why: AQI or pollutant levels are elevated, so this guidance is more cautious.
Philadelphia, Pennsylvania, United States
Philadelphia air quality today
Outdoor activity is generally possible, but conditions are not ideal.
Data: Hourly Open-Meteo model estimateThe latest update is older than expected, so this page is showing an estimate for the current hour.Detailed metrics and guidance use the latest available detailed data.
Practical guidance
Running
Outdoor running is generally fine. If you are sensitive to air pollution, consider keeping the effort easy.
Why: Air quality indicators are elevated, so the running guidance is more cautious.
Ventilation
Consider waiting before longer ventilation.
Why: PM2.5, PM10, NO2 or ozone is elevated, so longer ventilation may bring more outdoor pollution indoors.
Air quality and outdoor metrics
US AQI
Air Quality Index
58
Moderate
PM2.5
Fine particulate matter
14.6µg/m³
Moderate
PM10
Coarse particulate matter
14.7µg/m³
Low
NO₂
Nitrogen dioxide
24µg/m³
Low
O₃
Ozone
45µg/m³
Low
UV index
Sun exposure level
0
Low
Temperature
Air temperature
21°C
Comfortable
Feels like
Apparent temperature
22°C
Comfortable
Wind
Wind speed
6km/h
Light
Humidity
Relative humidity
71%
Humid
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Disclaimer
This information is a general estimate only and is not medical advice.
Location
Philadelphia, United States
Coordinates: 39.9526, -75.1652 · America/New_York
Interpret AQI for outdoor activity
Calculic's European AQI calculator assesses the value using your population group and planned activity intensity.
Interpret AQI in CalculicThis page's European AQI value, city and timestamp are passed to the calculator through the link.
What affects air quality in Philadelphia
Philadelphia Air Management Services' 2025 network assessment says vehicle and highway emissions are among the city's largest contributors, while the former PES area remains a PM2.5 hotspot with other major sources, including a nearby interstate highway.
The assessment combines 2018–2023 facility-inventory context with a qualitative hotspot discussion; it does not describe current concentrations, every neighborhood, or this site's current-data provenance.
Local monitoring and context
Philadelphia says its ambient network uses ten permanent air monitoring stations and a sensor-equipped van for additional areas.
The City describes separate station and van observations; no single monitor is treated as citywide, and this network is not the current-data provider for this page.
City air quality FAQ
How should I read the AQI for Philadelphia?
US AQI condenses air quality into one value. On this page, it helps you quickly judge whether conditions look good, moderate or more polluted than usual.
Is the air quality good for going outside?
Check the outdoor and running cards first. They combine AQI, particles, ozone, weather and other factors that can affect outdoor comfort.
Should I ventilate right now?
The ventilation card considers AQI and pollutants such as particles, nitrogen dioxide and ozone. If values are elevated, a shorter opening or a later moment may be better.
Why can air quality change during the day?
Weather, emissions, ozone formation, particles and air flow can shift local conditions, so the next hours can differ from the current reading.
Sources and methodology
Current data
This page uses US AQI.
Current and hourly air-quality values are CAMS-based model estimates, not measurements from a local monitoring station. They may not reflect street-level conditions.
- Displayed state
- This hour's model estimate
- Data time
- 5 Sept 2026, 09:00 pm
- Data source
- Open-Meteo
The latest update is older than expected, so this page is showing an estimate for the current hour.
Detailed metrics and guidance use the latest available detailed data.
Evergreen city statements
Each local statement is linked to a checked primary-authority source. A source check is editorial provenance and does not describe current-data freshness.
Local sources support the background claims below; they are not the source of the current data shown above unless explicitly stated otherwise.
Authoritative sources for local statements
2025 Five-Year Network Assessment of the Philadelphia Air Quality Surveillance System
City of Philadelphia — Department of Public Health, Air Management Services
- Scope
- Philadelphia
- Source checked
- 23 Aug 2026
PDF pages 20–21 explain that vehicle and highway emissions are among Philadelphia's largest contributors and retain the former PES area as a PM2.5 hotspot because other major sources, including a nearby interstate, remain.
Applicability: Official network assessment using 2018–2023 facility-inventory context; its source discussion is not a current concentration or current-data provenance statement.
Based on this source: Philadelphia Air Management Services' 2025 network assessment says vehicle and highway emissions are among the city's largest contributors, while the former PES area remains a PM2.5 hotspot with other major sources, including a nearby interstate highway.
Check air quality data
City of Philadelphia — Department of Public Health
- Scope
- Philadelphia
- Source checked
- 23 Aug 2026
The Philadelphia Air Monitoring Network section says ten permanent stations operate across the city and a sensor-equipped van supplies data in additional areas.
Applicability: Official city network description; station and mobile observations are spatially distinct and are not the current-data provenance for this page.
Based on this source: Philadelphia says its ambient network uses ten permanent air monitoring stations and a sensor-equipped van for additional areas.