Metro area air quality · 2025

Sheridan, WY

Median AQI 27 (Good). 89.1% of monitored days rated Good across this metro's EPA monitoring network.

27
Median AQI
89.1%
Good-air days
0
Unhealthy days
85%
Cleaner than US metros

Sheridan, WY posted a 2025 median AQI of 27 (Good) with 89.1% Good days

According to the U.S. EPA Air Quality System, the Sheridan, WY CBSA recorded a median AQI of 27 across 359 monitored days in 2025, with 89.1% rated Good and 0 unhealthy or worse. This is an annual metro comparison, not a live advisory.

Data source EPA Air Quality System (AQS)

Cleaner than US metros
The Sheridan, WY CBSA's 89.1% Good-day share places it cleaner than 85% of US metros in 2025.
Closest median-AQI peer
Aberdeen, SD (83.6% Good, median AQI 27) is the closest nationwide median-AQI peer to Sheridan, WY.
2020–2025 Good-day shift
Sheridan, WY's Good-day share moved -2.1 points from 2020 to 2025 (median AQI -13).
Median AQI
Median AQI: 27

Aggregated from EPA Air Quality System (2025), 359 monitored days. EPA AQS →

The verdict

Sheridan, WY sits in the upper Good-day tercile among EPA CBSA metros on this site (89.1% of 359 monitored days). On the EPA scale the metro runs good, cleaner than most US metros, with a median AQI of 27 and 89.1% of 359 monitored days in the Good band.

27
median AQI · Good
89.1%
days rated Good
85%
cleaner than US metros
75
worst single reading

No day crossed into the Unhealthy tier across the metro's monitors in 2025.

Annual release change

What changed in the 2025 EPA annual release

2024 → 2025
  • Sheridan, WY metro's peak single-day AQI fell from 205 to 75 between the 2024 and 2025 EPA annual releases, a change of -130 points.
  • Sheridan, WY metro's Good-day share rose from 78.9% to 89.1% between the 2024 and 2025 EPA annual releases, a change of +10.2 percentage points.
  • Sheridan, WY metro's Unhealthy-category days fell from 6 to 0 between the 2024 and 2025 EPA annual releases, a change of -6 days.
  • Sheridan, WY metro's median AQI fell from 44 to 27 between the 2024 and 2025 EPA annual releases, a change of -17 points.

Compared against 356 monitored days in 2024 and 359 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

Sheridan, WY sits in the upper Good-day tercile among EPA CBSA metros on this site (89.1% of 359 monitored days). Signature read: 89.1% Good-day share (high tercile vs CBSA corpus). Aggregated EPA AQS monitors across this Core-Based Statistical Area logged a median Air Quality Index of 27 over 359 measured days in 2025 (Good / Good). The monitored-day split lands at 320 Good (89%), 39 Moderate (11%), and 0 Unhealthy-for-Sensitive-Groups (0%). The 90th-percentile AQI finished at 51; the highest single-day reading hit 75 (Moderate).

Across 2020–2025, Good-day share shifted -2.1 points and median AQI moved -13 (improving). No Unhealthy-tier days appear in this annual dataset. Metros with comparable AQI profiles include Aberdeen, SD (83.6% good, AQI 27); Albany, OR (80.0% good, AQI 27); Anchorage, AK (77.5% good, AQI 27).

Best and worst city air quality →

Air Quality Summary

Median AQI

27

Good

Good Days

89.1%

320 of 359 days

Max AQI

75

Moderate

Health Grade

Good

90th pct: 51

AQI Day Breakdown (2025)

Distribution of 359 monitored days across EPA AQI categories.

Good

320

89%

Moderate

39

11%

USG

0

0%

Unhealthy

0

0%

Very Unhealthy

0

0%

Hazardous

0

0%

Health Impact Assessment

Good

The Sheridan, WY metro area's air quality is rated Good based on 89.1% good air days. No unhealthy air days were recorded in 2025.

Air quality is generally acceptable. Unusually sensitive people should monitor real-time conditions at AirNow.gov during high-pollution events.

How does the Sheridan, WY metro compare?

How Sheridan, WY compares

Good-day share better than typical
Sheridan, WY 89.1%
Aberdeen, SD 83.6%
Typical US metro 70.6%
Median AQI better than typical
Sheridan, WY 27
Aberdeen, SD 27
Typical US metro 41
Unhealthy days / yr better than typical
Sheridan, WY 0
Aberdeen, SD 0
Typical US metro 1

5-Year Air Quality Trend

Air quality is improving in the Sheridan, WY metro. Highest Good-day share: 2020 (91.3%, 334 of 366 monitored days).

Year Good Moderate Unhealthy Median AQI
2020 334 32 0 40
2021 302 55 0 40
2022 270 95 0 44
2023 283 79 1 43
2024 281 69 6 44
2025 320 39 0 27

Metros with a similar median AQI

CBSA peers nationwide whose annual median AQI sits near Sheridan, WY (27).

Aberdeen, SD

Median AQI 27 · 83.6% Good-day share

27

Albany, OR

Median AQI 27 · 80.0% Good-day share

27

Anchorage, AK

Median AQI 27 · 77.5% Good-day share

27

La Grande, OR

Median AQI 27 · 84.4% Good-day share

27

Olympia-Tumwater, WA

Median AQI 27 · 93.5% Good-day share

27

Utica-Rome, NY

Median AQI 27 · 84.4% Good-day share

27

Metros with similar unhealthy-day exposure

A second relationship type: metros whose unhealthy-or-worse day count is closest to Sheridan, WY's 0 (independent of median AQI).

Aberdeen, WA

0 unhealthy-or-worse days · median AQI 22

22

Adrian, MI

0 unhealthy-or-worse days · median AQI 41

41

Akron, OH

0 unhealthy-or-worse days · median AQI 45

45

Albany, GA

0 unhealthy-or-worse days · median AQI 46

46

Albany-Schenectady-Troy, NY

0 unhealthy-or-worse days · median AQI 41

41

Alexandria, LA

0 unhealthy-or-worse days · median AQI 37

37

Frequently Asked Questions

How many unhealthy air days does Sheridan, WY have? ▼
In 2025, the Sheridan, WY metro area recorded 0 unhealthy air days (0 Unhealthy, 0 Very Unhealthy, 0 Hazardous). The maximum AQI reached 75.
What is the air quality in the Sheridan, WY metro area? ▼
The Sheridan, WY metro area has a median Air Quality Index (AQI) of 27, rated "Good." 89.1% of monitored days (320 out of 359) had good air quality in 2025.
Is air quality in Sheridan, WY getting better or worse? ▼
Air quality in the Sheridan, WY metro is improving across floor-qualifying years (2020-2025); years with fewer than 100 monitored days are excluded from that direction. Highest qualifying Good-day share: 2020 at 91.3% (334 of 366 days). Lowest qualifying Good-day share: 2022 at 74.0% (270 of 365 days).
What does AQI 27 mean for health? ▼
An AQI of 27 is "Good", air quality is satisfactory and poses little or no health risk. This is the best category on the EPA's AQI scale.
How does Sheridan, WY compare to other metro areas? ▼
The Sheridan, WY metro has 89.1% good air days. Similar metros: Aberdeen, SD (83.6% good), Albany, OR (80.0% good), Anchorage, AK (77.5% good).
What is the 90th percentile AQI for Sheridan, WY? ▼
The 90th percentile AQI for the Sheridan, WY metro area is 51, meaning 90% of monitored days had an AQI at or below this level. The maximum AQI recorded was 75 (Moderate).

Data Sources

Primary Source: U.S. Environmental Protection Agency (EPA), Air Quality System (AQS), Annual AQI by CBSA dataset for Sheridan, WY, 2025. See our methodology for how AQI, median, and coverage figures are computed.

Read our methodology , how this data is sourced, computed, and verified.

Source: U.S. EPA Air Quality System (AQS) Annual AQI by CBSA summary, Sheridan, WY · 2020–2025