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  2. Outdoor Air Quality Data

Air Data - Daily Air Quality Tracker (PDF Report)

Use of AirNow Data

This plot provides ozone and PM2.5 data from AirNow for recent days that are not available from AQS. AQS data, as it becomes available, replaces any AirNow data. The AirNow data are not fully verified and validated through the quality assurance procedures monitoring organizations use to officially submit and certify data on the EPA AQS (Air Quality System) and, therefore, cannot be used to formulate or support regulation, guidance or any other Agency decision or position.

This report puts multiple AirData outputs on a single page to show:

  • Daily AQI values in 2024 relative to the previous 24-year high and low and the previous five-year average
  • Counts of "good" and "bad" AQI days in 2024 relative to the previous 24-year high and low and the previous five-year average
  • Distribution of daily AQI values in 2024 by calendar quarter relative to previous years

More information: The most recent AQI values are based on available ozone and PM2.5 data from AirNow (see "Use of AirNow Data" info box).  The 24-year high/low backdrop is based on AQS data from 2000-2023.  It shows the range of the highest and lowest daily max AQI values on each date.  The 5-year average is based on AQS data from 2019 -2023.  It  shows the average of daily max AQI values on each date. The distribution plots fit a normal density function to the data to convey spread and central tendency in each quarter relative to the same quarter in other years. In the tile plot, each tile represents one day and is color-coded based on the AQI level for that day.

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Outdoor Air Quality Data

  • Frequent Questions about AirData
  • Learn about Air Data
  • Interactive Map
  • Pre-generated Data Files
  • Download Daily Data
  • Download Raw Data (API)
  • Air Quality Index Report
  • Air Quality Statistics Report
  • Monitor Values Report
  • Monitor Values Report - Hazardous Air Pollutants
  • Air Quality Index Daily Values Report
  • Daily Air Quality Tracker
  • Tile Plot - Multiyear
  • Tile Plot - Single Year
  • AQI Plot
  • Concentration Plot
  • Ozone Exceedances
  • Concentration Map
  • PM2.5 Continuous Monitor Comparability Assessments
  • PM10 Continuous Monitor Comparability Assessments
  • Single Point Precision & Bias Report
Contact Us about Outdoor Air Quality Data
Contact Us to ask a question, provide feedback, or report a problem.
Last updated on May 2, 2025
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