Air quality · Tennessee
Air quality in Tennessee
Across the 8 Tennessee ZIPs with EPA county air-quality data, the median day is Good in all 8 (median AQI 40–49). 1 day across those counties reached Unhealthy or worse in 2025. This is a 2025 county annual summary, not a live reading.
Last verified 2026-09-24 · methodology
Air quality by ZIP code in Tennessee
EPA's 2025 annual summary for each ZIP's county. Median AQI is the typical day; lower is cleaner.
| ZIP | Median AQI | Good days | Unhealthy or worse |
|---|---|---|---|
| 37203NashvilleDavidson County | 49 Good | 193 of 365 | 0 |
| 38103MemphisShelby County | 47 Good | 220 of 365 | 0 |
| 37919KnoxvilleKnox County | 46 Good | 230 of 365 | 1 |
| 37027Brentwood (TN)Williamson County | 40 Good | 216 of 243 | 0 |
| 37067Franklin (TN)Williamson County | 40 Good | 216 of 243 | 0 |
| 37212Nashville (Music Row)Davidson County | 49 Good | 193 of 365 | 0 |
| 38104Memphis (Midtown)Shelby County | 47 Good | 220 of 365 | 0 |
| 37205Nashville (Belle Meade)Davidson County | 49 Good | 193 of 365 | 0 |
County-level figures from EPA Air Quality System (AQS), annual county summary, joined to each ZIP by county. None of them is a measurement at a specific address.
What lands here
Pages show the 2025 median AQI category (Good, Moderate, Unhealthy for Sensitive Groups, Unhealthy, Very Unhealthy, Hazardous) for the ZIP's county, plus the year's max/90th-percentile AQI and day-count breakdown by category.
Source & refresh
EPA Air Quality System (AQS), annual county summary. Refreshed annual (epa aqs publication). Primary source →
Tennessee top concern
Tornadoes, flood (TVA tributaries), karst sinkholes
Tennessee carries inland FEMA AE zones along TVA-managed Tennessee, Cumberland, Holston rivers. Karst geology creates documented sinkhole risk in middle TN. Tornado risk concentrates in Memphis + Jackson + Nashville corridors.
See Tennessee state page for the full state-level rollup across all 12 dimensions.
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