Baltimore Air Quality in April
Across 2019–2025, Baltimore's April air quality had a median AQI of 47 (Good) over 210 monitored days in the Baltimore-Columbia-Towson, MD area. 0.5% of April days (1 of 210) reached Unhealthy for Sensitive Groups or worse, and ground-level ozone set the daily AQI on 82.9% of days. The cleanest April on record here was 2022 (median AQI 44, 0 days above 100) and the worst was 2023 (median 53, 1 day above 100, peak AQI 112).
- Good: 64.3%
- Moderate: 35.2%
- Unhealthy for Sensitive Groups: 0.5%
- Unhealthy or worse: 0.0%
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How is the air in Baltimore in April?
Good on a typical day: median AQI 47 across 2019–2025, with 0.5% of April days above AQI 100. Ground-level ozone is the main driver.
- ✓64.3% of April days were Good (AQI 0–50), 35.2% Moderate (51–100).
- ✓1 day of 210 reached AQI 101+; the April peak was 112.
- ✓Best April: 2022; worst April: 2023.
Frequently asked questions
What is the air quality like in Baltimore in April?▾
Across 2019–2025, the median daily AQI in Baltimore in April was 47 (Good). 64.3% of days were Good, 35.2% Moderate, and 0.5% reached Unhealthy for Sensitive Groups or worse, based on 210 monitored days in EPA's Air Quality System.
Is April a good time for outdoor exercise in Baltimore?▾
A typical April day in Baltimore sits in the Good range (median AQI 47), so running, cycling and children's outdoor play are fine for everyone on most days; fewer than 1% of April days reached AQI 101+ in 2019–2025.
Which pollutant causes Baltimore's April air quality problems?▾
Ground-level ozone set the daily AQI on 82.9% of April days in Baltimore. The highest April AQI recorded in 2019–2025 was 112 (Unhealthy for Sensitive Groups), in 2023.
Baltimore April air quality, year by year
Baltimore April air quality by year (Baltimore-Columbia-Towson, MD, EPA AQS daily AQI)
| Year | Days monitored | Median AQI | Days above 100 | Peak AQI | Main pollutant |
|---|---|---|---|---|---|
| 2019 | 30 | 46 | 0 | 67 | O3 |
| 2020 | 30 | 46 | 0 | 59 | O3 |
| 2021 | 30 | 51 | 0 | 87 | O3 |
| 2022cleanest | 30 | 44 | 0 | 67 | O3 |
| 2023worst | 30 | 53 | 1 | 112 | O3 |
| 2024 | 30 | 47 | 0 | 97 | O3 |
| 2025 | 30 | 46 | 0 | 84 | O3 |
What April air means in Baltimore
A typical April day in Baltimore sits in the Good range (median AQI 47), so running, cycling and children's outdoor play are fine for everyone on most days; fewer than 1% of April days reached AQI 101+ in 2019–2025.
April's median AQI of 47 is in line with Baltimore's whole-year median of 49, so this period is neither a clean nor a dirty stretch for the area. Nationally, the median April AQI across every EPA metro area (100,677 metro-days, 2019–2025) is 44, so Baltimore runs in line with the national April norm; 0.5% of its April days topped AQI 100 versus 0.7% nationally (about the same).
April is part of Baltimore's spring season (March, April, May); the spring page pools all three months.
Activity-specific thresholds: running, cycling, kids' sports.
Right now in Baltimore
The latest EPA AirNow observation puts Baltimore's AQI at 43 (PM2.5). The figures above are multi-year month statistics, not today's reading.
View current Baltimore air quality →Source: EPA Air Quality System (AQS) pre-generated Daily AQI by CBSA files — daily AQI by CBSA (Baltimore-Columbia-Towson, MD), 2019–2025. Daily AQI per CBSA is the highest AQI reported by any monitor in the area that day; the defining parameter is the pollutant that set it. Month and season statistics pool every such day in the period across all years listed. Retrieved 2026-09-09.