Kentucky · County air quality · 2025

Daviess County, Kentucky

Median AQI 43 (Good). 61.9% of monitored days rated Good, direct from EPA Air Quality System stations.

43
Median AQI
61.9%
Good-air days
0
Unhealthy days
17%
Cleaner than US counties

Daviess County's 2025 annual median AQI is 43 (Good), with 61.9% Good days

According to the U.S. EPA Air Quality System, Daviess County, Kentucky posted a 2025 median AQI of 43 (Good) across 365 monitored days, with 61.9% rated Good and 0 unhealthy or worse. This is an annual comparison, not today's advisory.

Data source EPA Air Quality System (AQS)

Cleaner than US
Daviess County's 61.9% Good-day share places it cleaner than 17% of US counties in 2025.
Closest median-AQI peer
Ashtabula County (81.2% Good, median AQI 43) is the closest nationwide median-AQI peer to Daviess County.
2020–2025 trend
Daviess County's floor-qualifying Good-day share is worsening from 2020 to 2025 (69.4% → 61.9%).
Median AQI
Median AQI: 43

According to the 2025 EPA AQS county release on PlainAirData, Daviess County, Kentucky ranks #631 of 951 by median AQI (43) and #782 by good-day share (61.9%). Ponce County, Puerto Rico is #1 of 951 by median AQI (3, 91.4% Good days) at good-day-share #159 ≠ largest of 7 at 100.0% Good days #1 by good-day share (100.0%, median AQI 9) at median-AQI #7.

Annual release change

What changed in the 2025 EPA annual release

2023 → 2025
  • Daviess County's Good-day share rose from 45.4% to 61.9% between the 2023 and 2025 EPA annual releases, a change of +16.5 percentage points.
  • Daviess County's peak single-day AQI fell from 170 to 84 between the 2023 and 2025 EPA annual releases, a change of -86 points.
  • Daviess County's median AQI fell from 51 to 43 between the 2023 and 2025 EPA annual releases, a change of -8 points.
  • Daviess County's Unhealthy-category days fell from 1 to 0 between the 2023 and 2025 EPA annual releases, a change of -1 days.

Compared against 218 monitored days in 2023 and 365 in 2025. These are arithmetic differences between two stored EPA annual summaries, not a cause claim or a live advisory.

National release changes Two-year CSV

Data updated August 2026

Daviess County AQI category distribution Stacked-segment bar showing the share of monitored days that fell in each EPA AQI category, Good, Moderate, USG, Unhealthy, Very Unhealthy, Hazardous, with median AQI marker. AQI category distribution 365 monitored days G M Median AQI 43 0 50 100 150 200 300 500 Daviess County
  • Good · 226 d · 61.9%
  • Moderate · 139 d · 38.1%

How did Daviess County's air break down in 2025?

Across 365 monitored days, 226 fell in the Good band (AQI 0–50) and 0 reached Unhealthy or worse. The worst single day peaked at AQI 84 (Moderate).

EPA AQS →
Daviess County, Good days share 61.9%
National avg

Share of monitored days at AQI 0-50 (Good band).

Daviess County, Unhealthy-or-worse share 0.0%
National avg

Share of monitored days above AQI 150 (Unhealthy or worse). Bar maxes at 10% (worst-county ceiling).

Where Daviess County sits nationally

COUNT-derived placement among 951 US counties with at least 100 monitored days in 2025. Daviess County's Good-day share is 61.9% - cleaner than 17% of that comparison set.

Daviess County Good-day share vs. every US county

Share of monitored days in the Good band (AQI 0–50) - EPA AQS annual release

61.9% 17th percentile higher than 17% of 951 US counties

0.0%–5.0%: 0 US counties (0%). Below this entry. 5.0%–10.0%: 1 US counties (0%). Below this entry. 10.0%–15.0%: 4 US counties (0%). Below this entry. 15.0%–20.0%: 4 US counties (0%). Below this entry. 20.0%–25.0%: 1 US counties (0%). Below this entry. 25.0%–30.0%: 5 US counties (1%). Below this entry. 30.0%–35.0%: 9 US counties (1%). Below this entry. 35.0%–40.0%: 4 US counties (0%). Below this entry. 40.0%–45.0%: 16 US counties (2%). Below this entry. 45.0%–50.0%: 16 US counties (2%). Below this entry. 50.0%–55.0%: 32 US counties (3%). Below this entry. 55.0%–60.0%: 50 US counties (5%). Below this entry. 60.0%–65.0%: 77 US counties (8%). This entry sits in this band. 65.0%–70.0%: 93 US counties (10%). Above this entry. 70.0%–75.0%: 109 US counties (11%). Above this entry. 75.0%–80.0%: 114 US counties (12%). Above this entry. 80.0%–85.0%: 123 US counties (13%). Above this entry. 85.0%–90.0%: 99 US counties (10%). Above this entry. 90.0%–95.0%: 117 US counties (12%). Above this entry. 95.0%–100.0%: 70 US counties (7%). Above this entry. 100.0%–105.0%: 7 US counties (1%). Above this entry. This county 0.0% 100% every floor-qualified US county, bucketed by value

Each bar is a band; taller bars hold more US counties. The dashed line + filled bar mark this entry. Hover or tap any bar for its full count, share, and where it sits relative to this entry.

Source U.S. Environmental Protection Agency, Air Quality System (AQS) · 2025

Pollutant Breakdown

Days where each pollutant was the primary driver of AQI readings in Daviess County.

Daviess County, Kentucky criteria pollutant distribution Stratified-band visualization showing the share of monitored days each criteria pollutant (PM2.5, PM10, O3, NO2, CO) was the primary AQI driver. PM2.5 · 72.1% Ozone · 27.9% 0% 25% 50% 75% 100% Daviess County, Kentucky · 365 monitored days Criteria pollutant column
  • PM2.5 · 263 days · 72.1%
  • Ozone · 102 days · 27.9%

Five-year seasonal record

EPA day-level county files · 2020–2024

1,352 daily readings show a recurring local pattern: Jun has the highest matched-month median AQI (58), while Sep is lowest (40). Each cell is that month’s median daily AQI, not a current-air forecast.

JanFebMarAprMayJunJulAugSepOctNovDec
2020 414138453951464239394157
2021 485144494444615142554753
2022 524846424651464340415350
2023 5141515251845140----
2024 ----------4632

Lower AQI is better. The colors summarize EPA AQI bands; gaps mean the county had no day-level record for that month.

Health Impact Assessment

Moderate

Daviess County's air quality is rated Moderate based on 61.9% good air days. No unhealthy air days were recorded in 2025.

Air quality was acceptable on 61.9% of monitored days in 2025, with a median AQI of 43. Unusually sensitive people can check real-time conditions at AirNow.gov during high-pollution events.

The dominant pollutant is PM2.5, driving AQI on 263 of 365 monitored days.

5-Year Air Quality Trend

Air quality is worsening in Daviess County. Highest Good-day share: 2020 (69.4%, 254 of 366 monitored days).

Year Good Moderate USG Unhealthy Median AQI
2020 254 111 1 0 43
2021 200 163 0 0 48
2022 230 135 0 0 46
2023 99 110 8 1 51
2024 31 9 0 0 37
2025 226 139 0 0 43

How does Daviess County compare?

How Daviess County compares

Good-day share worse than typical
Daviess County 61.9%
Ashtabula County, Ohio 81.2%
Typical US county 76.0%
Median AQI worse than typical
Daviess County 43
Ashtabula County, Ohio 43
Typical US county 39
Unhealthy days / yr better than typical
Daviess County 0
Ashtabula County, Ohio 0
Typical US county 1

Data Sources

Primary Source: U.S. Environmental Protection Agency (EPA), Air Quality System (AQS), Annual AQI by County dataset, 2020–2025 (aqs.epa.gov). For current conditions (not shown here — this page is historical annual data), see EPA AirNow (airnow.gov). See our methodology for how AQI, median, and coverage figures are computed.

Informational only, not professional advice. Data from EPA AQS. See our disclaimer. Spotted a figure that looks wrong? Report a correction.

Source: U.S. EPA Air Quality System (AQS) Annual AQI by county summary files for Daviess County, Kentucky · 2020–2025

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Download this county's annual AQI row as CSV , with the same EPA fields and denominator shown on this page.

Every figure on PlainAirData is rendered directly from EPA AQS air-quality monitoring data, no number is typed in by an editor. This page draws directly on EPA AQS air-quality monitoring data, no figure is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error.