Metro area air quality · 2024

Altoona, PA

Median AQI 37 (Good). 80.9% of monitored days rated Good across this metro's EPA monitoring network.

37
Median AQI
80.9%
Good-air days
0
Unhealthy days
67%
Cleaner than US metros

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

Insights: Altoona, PA metro. Aggregated EPA AQS monitors across this Core-Based Statistical Area logged a median Air Quality Index of 37 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 296 Good days (81%), 70 Moderate (19%), and 0 Unhealthy-for-Sensitive-Groups (0%). The 90th-percentile AQI finished at 58 while the highest single-day reading hit 100 (Moderate). Metro residents averaged roughly 24.3 clean-air days per 30-day window across the reporting year.

Across the 2020–2024 trend window, good days shifted by +34 and the median AQI moved -6 points, which classifies the multi-year trajectory as improving. 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 Albany-Schenectady-Troy, NY (76.5% good, AQI 37); Appleton, WI (79.5% good, AQI 37); Baraboo, WI (85.3% good, AQI 37).

Air Quality Summary

Median AQI

37

Good

Good Days

80.9%

296 of 366 days

Max AQI

100

Moderate

Health Grade

Good

90th pct: 58

AQI Day Breakdown (2024)

Distribution of 366 monitored days across EPA AQI categories.

Good

296

81%

Moderate

70

19%

USG

0

0%

Unhealthy

0

0%

Very Unhealthy

0

0%

Hazardous

0

0%

Health Impact Assessment

Good

The Altoona, PA metro area's air quality is rated Good based on 80.9% 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 Altoona, PA metro compare?

How Altoona, PA compares

Good-day share better than US avg
Altoona, PA 80.9%
Albany-Schenectady-Troy, NY 76.5%
US average 70.2%
Median AQI better than US avg
Altoona, PA 37
Albany-Schenectady-Troy, NY 37
US average 41
Unhealthy days / yr better than US avg
Altoona, PA 0
Albany-Schenectady-Troy, NY 0
US average 1

5-Year Air Quality Trend

Air quality is improving in the Altoona, PA metro. Best year: 2024 (296 good days).

Year Good Moderate Unhealthy Median AQI
2020 262 98 0 43
2021 206 128 0 45
2022 234 129 0 44
2023 229 123 4 43
2024 296 70 0 37

Metros with Similar Air Quality

Metro areas across the US with a similar median AQI to Altoona, PA.

Albany-Schenectady-Troy, NY

AQI 37 · 76.5% good

37

Appleton, WI

AQI 37 · 79.5% good

37

Baraboo, WI

AQI 37 · 85.3% good

37

Bay City, MI

AQI 37 · 76.3% good

37

Burlington-South Burlington, VT

AQI 37 · 88.3% good

37

Cape Coral-Fort Myers, FL

AQI 37 · 92.1% good

37

More Air Quality Data

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Worst Air Quality

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All Metro Areas

Annual AQI by CBSA for every monitored U.S. metro area.

Best and Worst City Air

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Air Quality Guides

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

Understanding AQI

What each AQI level means and who is most at risk.

Best & Worst City Air Quality

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Health Effects of Air Pollution

How PM2.5 and ozone exposure affects respiratory and cardiovascular health.

Frequently Asked Questions

What is the air quality in the Altoona, PA metro area? ▼
The Altoona, PA metro area has a median Air Quality Index (AQI) of 37, rated "Good." 80.9% of monitored days (296 out of 366) had good air quality in 2024.
How many unhealthy air days does Altoona, PA have? ▼
In 2024, the Altoona, PA metro area recorded 0 unhealthy air days (0 Unhealthy, 0 Very Unhealthy, 0 Hazardous). The maximum AQI reached 100.
Is air quality in Altoona, PA getting better or worse? ▼
Air quality in the Altoona, PA metro is improving based on 5-year trends (2020-2024). Best year: 2024 with 296 good days. Worst year: 2021 with 206 good days.
What does AQI 37 mean for health? ▼
An AQI of 37 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 Altoona, PA? ▼
The 90th percentile AQI for the Altoona, PA metro area is 58, meaning 90% of monitored days had an AQI at or below this level. The maximum AQI recorded was 100 (Moderate).
How does Altoona, PA compare to other metro areas? ▼
The Altoona, PA metro has 80.9% good air days. Similar metros: Albany-Schenectady-Troy, NY (76.5% good), Appleton, WI (79.5% good), Baraboo, WI (85.3% 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.

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

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