Air Quality - National Weather Service
Philadelphia Mt Holly NJ PA DE MD Air Quality
www.weather.govHere’s the latest on Air Quality Index (AQI) and how to interpret current conditions.
Key points
- AQI is the public-facing scale used in the United States to summarize daily air quality for common pollutants (ozone, PM2.5, PM10, CO, NO2, SO2). It uses color categories to indicate health risk levels and provides guidance on outdoor activity and exposure.[1][6]
- Real-time and forecasted AQI data are published by authoritative sources such as AirNow (U.S. EPA) and state/local air quality agencies. These sources offer current maps, city-by-city readings, and daily forecasts to help you plan outdoor activities.[4][5][6]
What’s in the latest updates
- Current conditions: Expect to see a city- or region-specific AQI value with a category (Good, Moderate, Unhealthy for Sensitive Groups, Unhealthy, Very Unhealthy, or Hazardous). The exact numbers and colors are updated continuously as measurements come in from monitoring networks.[6]
- NowCast: In addition to daily AQI, NowCast estimates provide a near-real-time snapshot for ozone and fine particle pollution, based on hourly monitors, to reflect current exposure risk more accurately than the daily average alone.[1]
- Public guidance: If AQI is in the Moderate-to-Unhealthy range, sensitive groups (children, older adults, people with respiratory or heart conditions) may want to limit strenuous outdoor activity and check local advisories. For higher categories, the guidance escalates to reducing outdoor exertion or staying indoors with air filtration where possible.[2][9]
How to check for your area right now
- Use AirNow or your local environmental or weather service to view the latest AQI: current AQI by city, state, and nationwide forecasts. These pages provide color-coded maps, pollutant-specific AQIs, and health recommendations for your location.[5][4][6]
- For a quick sense of global or regional trends, you can also view real-time maps from major aggregators, but always cross-check with official sources for local health advisories and exact readings.[2][6]
Illustrative example
- If your neighborhood has an AQI of 75 in the Moderate category, outdoor activities are generally considered acceptable for most people, but those unusually sensitive to air pollution might choose to shorten outdoor time or plan activities for times when air quality improves; kids and adults with respiratory issues should monitor symptoms closely.[6][2]
Would you like me to pull the current AQI for a specific city (e.g., New York City, NYC) and provide the category, main pollutant, and recommended actions? If yes, tell me the location you want. I’ll give you the latest numbers and guidance with direct citations.[4][1][6]