Metro area air quality · 2024

Brookings, SD

Median AQI 36 (Good). 79.8% of monitored days rated Good across this metro's EPA monitoring network.

36
Median AQI
79.8%
Good-air days
0
Unhealthy days
64%
Cleaner than US metros

Aggregated from EPA Air Quality System (2024), 366 monitored days. EPA AQS → · NOAA →

Insights: Brookings, SD metro. Aggregated EPA AQS monitors across this Core-Based Statistical Area logged a median Air Quality Index of 36 over 366 measured days in 2024, which corresponds to a Good band and a Good metro-wide health grade. The monitored-day split lands at 292 Good days (80%), 72 Moderate (20%), and 2 Unhealthy-for-Sensitive-Groups (1%). The 90th-percentile AQI finished at 56 while the highest single-day reading hit 111 (USG). Metro residents averaged roughly 23.9 clean-air days per 30-day window across the reporting year.

Across the 2020–2024 trend window, good days shifted by -13 and the median AQI moved -3 points, which classifies the multi-year trajectory as worsening. The metro avoided any Unhealthy-tier days entirely, an outcome that typically reflects favorable wind patterns, lower industrial density, or effective regional emission controls. Metros with comparable AQI profiles include Barnstable Town, MA (94.3% good, AQI 36); Bemidji, MN (84.2% good, AQI 36); Bennington, VT (91.0% good, AQI 36).

Air Quality Summary

Median AQI

36

Good

Good Days

79.8%

292 of 366 days

Max AQI

111

USG

Health Grade

Good

90th pct: 56

AQI Day Breakdown (2024)

Distribution of 366 monitored days across EPA AQI categories.

Good

292

80%

Moderate

72

20%

USG

2

1%

Unhealthy

0

0%

Very Unhealthy

0

0%

Hazardous

0

0%

Health Impact Assessment

Good

The Brookings, SD metro area's air quality is rated Good based on 79.8% good air days. No unhealthy air days were recorded in 2024.

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

How does the Brookings, SD metro compare?

How Brookings, SD compares

Good-day share better than US avg
Brookings, SD 79.8%
Barnstable Town, MA 94.3%
US average 70.2%
Median AQI better than US avg
Brookings, SD 36
Barnstable Town, MA 36
US average 41
Unhealthy days / yr better than US avg
Brookings, SD 0
Barnstable Town, MA 0
US average 1

5-Year Air Quality Trend

Air quality is worsening in the Brookings, SD metro. Best year: 2022 (320 good days).

Year Good Moderate Unhealthy Median AQI
2020 305 61 0 39
2021 270 87 1 39
2022 320 44 0 36
2023 274 84 2 42
2024 292 72 0 36

Metros with Similar Air Quality

Metro areas across the US with a similar median AQI to Brookings, SD.

More Air Quality Data

Explore EPA air quality rankings and guides across U.S. metros and counties.

Air Quality Guides

Learn more about air quality monitoring, pollutants, and health impacts.

Frequently Asked Questions

What is the air quality in the Brookings, SD metro area?
The Brookings, SD metro area has a median Air Quality Index (AQI) of 36, rated "Good." 79.8% of monitored days (292 out of 366) had good air quality in 2024.
How many unhealthy air days does Brookings, SD have?
In 2024, the Brookings, SD metro area recorded 0 unhealthy air days (0 Unhealthy, 0 Very Unhealthy, 0 Hazardous). The maximum AQI reached 111.
Is air quality in Brookings, SD getting better or worse?
Air quality in the Brookings, SD metro is worsening based on 5-year trends (2020-2024). Best year: 2022 with 320 good days. Worst year: 2021 with 270 good days.
What does AQI 36 mean for health?
An AQI of 36 is "Good", air quality is satisfactory and poses little or no health risk. This is the best category on the EPA's AQI scale.
What is the 90th percentile AQI for Brookings, SD?
The 90th percentile AQI for the Brookings, SD metro area is 56, meaning 90% of monitored days had an AQI at or below this level. The maximum AQI recorded was 111 (USG).
How does Brookings, SD compare to other metro areas?
The Brookings, SD metro has 79.8% good air days. Similar metros: Barnstable Town, MA (94.3% good), Bemidji, MN (84.2% good), Bennington, VT (91.0% good).

Data Sources

Primary Source: U.S. Environmental Protection Agency (EPA), Air Quality System (AQS), Annual AQI by CBSA dataset, 2020–2024. The AQS collects ambient air monitoring data from state, local, and tribal monitoring agencies across the United States.

Metrics: Air Quality Index (AQI) is calculated using EPA-standard breakpoints for six criteria pollutants: PM2.5, PM10, Ozone, NO2, CO, and SO2. Median AQI, max AQI, and 90th percentile AQI are computed from daily measurements. Good days percentage reflects days with AQI 0–50.

Coverage: 501 metro areas (Core Based Statistical Areas). Only metros with active monitoring stations are included. Unmonitored areas are not represented.

Source: U.S. EPA, AirNow / AQS Air Quality Index readings and pollutant concentrations · 2025