Kansas · County air quality · 2025
Sherman County, Kansas
Median AQI 27 (Good). 90.1% of monitored days rated Good, direct from EPA Air Quality System stations.
- 27
- Median AQI
- 90.1%
- Good-air days
- 0
- Unhealthy days
- 80%
- Cleaner than US counties
Sherman County's 2025 annual median AQI is 27 (Good), with 90.1% Good days
According to the U.S. EPA Air Quality System, Sherman County, Kansas posted a 2025 median AQI of 27 (Good) across 333 monitored days, with 90.1% 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
- Sherman County's 90.1% Good-day share places it cleaner than 80% of US counties in 2025.
- Closest median-AQI peer
- Brown County (83.6% Good, median AQI 27) is the closest nationwide median-AQI peer to Sherman County.
- 2020–2025 trend
- Sherman County's floor-qualifying Good-day share is worsening from 2020 to 2025 (93.1% → 90.1%).
- Median AQI
- Median AQI: 27
According to the 2025 EPA AQS county release on PlainAirData, Sherman County, Kansas ranks #70 of 951 by median AQI (27) and #194 by good-day share (90.1%). 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
- Sherman County's Good-day share rose from 83.6% to 90.1% between the 2024 and 2025 EPA annual releases, a change of +6.4 percentage points.
- Sherman County's peak single-day AQI fell from 138 to 93 between the 2024 and 2025 EPA annual releases, a change of -45 points.
Data updated August 2026
- Good · 300 d · 90.1%
- Moderate · 33 d · 9.9%
How did Sherman County's air break down in 2025?
Across 333 monitored days, 300 fell in the Good band (AQI 0–50) and 0 reached Unhealthy or worse. The worst single day peaked at AQI 93 (Moderate).
EPA AQS →Share of monitored days at AQI 0-50 (Good band).
Share of monitored days above AQI 150 (Unhealthy or worse). Bar maxes at 10% (worst-county ceiling).
Where Sherman County sits nationally
COUNT-derived placement among 951 US counties with at least 100 monitored days in 2025. Sherman County's Good-day share is 90.1% - cleaner than 80% of that comparison set.
Sherman County Good-day share vs. every US county
Share of monitored days in the Good band (AQI 0–50) - EPA AQS annual release
90.1% Cleaner than 80% higher than 80% of 951 US counties
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 Sherman County.
- PM2.5 · 251 days · 75.4%
- PM10 · 82 days · 24.6%
2024 daily-monitor rhythm in Sherman County
Month-by-month median AQI from EPA day-level county monitors (324 reported days in 2024). Oct posted the highest typical readings (median AQI 58, peak 97); Nov was cleanest at median 18. Summer months (Jun–Aug) averaged median AQI 37 vs 19 in Dec–Feb.
Five-year seasonal record
EPA day-level county files · 2020–20241,641 daily readings show a recurring local pattern: Oct has the highest matched-month median AQI (35), while Jan is lowest (10). Each cell is that month’s median daily AQI, not a current-air forecast.
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
Sherman County's air quality is rated Excellent based on 90.1% good air days. No unhealthy air days were recorded in 2025.
Air quality was acceptable on 90.1% of monitored days in 2025, with a median AQI of 27. Unusually sensitive people can check real-time conditions at AirNow.gov during high-pollution events.
The dominant pollutant is PM2.5, driving AQI on 251 of 333 monitored days.
5-Year Air Quality Trend
Air quality is worsening in Sherman County. Highest Good-day share: 2021 (96.6%, 308 of 320 monitored days).
| Year | Good | Moderate | USG | Unhealthy | Median AQI | Max AQI |
|---|---|---|---|---|---|---|
| 2020 | 282 | 20 | 1 | 0 | 13 | 106 |
| 2021 | 308 | 11 | 0 | 0 | 17 | 221 |
| 2022 | 338 | 18 | 3 | 0 | 18 | 494 |
| 2023 | 315 | 19 | 0 | 0 | 19 | 78 |
| 2024 | 271 | 51 | 2 | 0 | 27 | 138 |
| 2025 | 300 | 33 | 0 | 0 | 27 | 93 |
How does Sherman County compare?
How Sherman County compares
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 Sherman County, Kansas · 2020–2025
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.