Metro area air quality · 2025

Rapid City, SD

Median AQI 47 (Good). 62.2% of monitored days rated Good across this metro's EPA monitoring network.

47
Median AQI
62.2%
Good-air days
0
Unhealthy days
29%
Cleaner than US metros

Rapid City, SD posted a 2025 median AQI of 47 (Good) with 62.2% Good days

According to the U.S. EPA Air Quality System, the Rapid City, SD CBSA recorded a median AQI of 47 across 365 monitored days in 2025, with 62.2% 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 Rapid City, SD CBSA's 62.2% Good-day share places it cleaner than 29% of US metros in 2025.
Closest median-AQI peer
Charleston-North Charleston, SC (60.3% Good, median AQI 47) is the closest nationwide median-AQI peer to Rapid City, SD.
2020–2025 Good-day shift
Rapid City, SD's Good-day share moved -6.9 points from 2020 to 2025 (median AQI +3).
Median AQI
Median AQI: 47

Aggregated from EPA Air Quality System (2025), 365 monitored days. EPA AQS →

The verdict

Rapid City, SD lands in the lower Good-day tercile (62.2% Good), a thinner clean-air share than most CBSA peers here. On the EPA scale the metro runs good, more polluted than the median US metro, with a median AQI of 47 and 62.2% of 365 monitored days in the Good band.

47
median AQI · Good
62.2%
days rated Good
29%
cleaner than US metros
107
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
  • Rapid City, SD metro's Good-day share rose from 52.5% to 62.4% between the 2024 and 2025 EPA annual releases, a change of +9.8 percentage points.
  • Rapid City, SD metro's peak single-day AQI fell from 154 to 107 between the 2024 and 2025 EPA annual releases, a change of -47 points.
  • Rapid City, SD metro's median AQI fell from 50 to 47 between the 2024 and 2025 EPA annual releases, a change of -3 points.
  • Rapid City, SD metro's Unhealthy-category days fell from 1 to 0 between the 2024 and 2025 EPA annual releases, a change of -1 days.

Compared against 354 monitored days in 2024 and 364 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

Rapid City, SD lands in the lower Good-day tercile (62.2% Good), a thinner clean-air share than most CBSA peers here. Signature read: 62.2% Good-day share (low tercile vs CBSA corpus). Aggregated EPA AQS monitors across this Core-Based Statistical Area logged a median Air Quality Index of 47 over 365 measured days in 2025 (Good / Moderate). The monitored-day split lands at 227 Good (62%), 137 Moderate (38%), and 1 Unhealthy-for-Sensitive-Groups (0%). The 90th-percentile AQI finished at 67; the highest single-day reading hit 107 (USG).

Across 2020–2025, Good-day share shifted -6.9 points and median AQI moved +3 (worsening). No Unhealthy-tier days appear in this annual dataset. Metros with comparable AQI profiles include Charleston-North Charleston, SC (60.3% good, AQI 47); Columbia, SC (58.1% good, AQI 47); Corsicana, TX (59.2% good, AQI 47).

Health effects of air pollution →

Air Quality Summary

Median AQI

47

Good

Good Days

62.2%

227 of 365 days

Max AQI

107

USG

Health Grade

Moderate

90th pct: 67

AQI Day Breakdown (2025)

Distribution of 365 monitored days across EPA AQI categories.

Good

227

62%

Moderate

137

38%

USG

1

0%

Unhealthy

0

0%

Very Unhealthy

0

0%

Hazardous

0

0%

Health Impact Assessment

Moderate

The Rapid City, SD metro area's air quality is rated Moderate based on 62.2% 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 Rapid City, SD metro compare?

How Rapid City, SD compares

Good-day share worse than typical
Rapid City, SD 62.2%
Charleston-North Charleston, SC 60.3%
Typical US metro 70.6%
Median AQI worse than typical
Rapid City, SD 47
Charleston-North Charleston, SC 47
Typical US metro 41
Unhealthy days / yr better than typical
Rapid City, SD 0
Charleston-North Charleston, SC 0
Typical US metro 1

5-Year Air Quality Trend

Air quality is worsening in the Rapid City, SD metro. Highest Good-day share: 2020 (69.2%, 252 of 364 monitored days).

Year Good Moderate Unhealthy Median AQI
2020 252 112 0 44
2021 225 128 1 45
2022 199 163 0 49
2023 189 164 6 50
2024 186 167 1 50
2025 227 137 0 47

Metros with a similar median AQI

CBSA peers nationwide whose annual median AQI sits near Rapid City, SD (47).

Metros with similar unhealthy-day exposure

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

Frequently Asked Questions

How many unhealthy air days does Rapid City, SD have?
In 2025, the Rapid City, SD metro area recorded 0 unhealthy air days (0 Unhealthy, 0 Very Unhealthy, 0 Hazardous). The maximum AQI reached 107.
What is the air quality in the Rapid City, SD metro area?
The Rapid City, SD metro area has a median Air Quality Index (AQI) of 47, rated "Good." 62.2% of monitored days (227 out of 365) had good air quality in 2025.
Is air quality in Rapid City, SD getting better or worse?
Air quality in the Rapid City, SD metro is worsening 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 69.2% (252 of 364 days). Lowest qualifying Good-day share: 2024 at 52.5% (186 of 354 days).
What does AQI 47 mean for health?
An AQI of 47 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 Rapid City, SD compare to other metro areas?
The Rapid City, SD metro has 62.2% good air days. Similar metros: Charleston-North Charleston, SC (60.3% good), Columbia, SC (58.1% good), Corsicana, TX (59.2% good).
What is the 90th percentile AQI for Rapid City, SD?
The 90th percentile AQI for the Rapid City, SD metro area is 67, meaning 90% of monitored days had an AQI at or below this level. The maximum AQI recorded was 107 (USG).

Data Sources

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

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