Hartford Air Quality in March
Across 2019–2025, Hartford's March air quality had a median AQI of 43 (Good) over 217 monitored days in the Hartford-West Hartford-East Hartford, CT area. 0.0% of March days (0 of 217) reached Unhealthy for Sensitive Groups or worse, and ground-level ozone set the daily AQI on 71.0% of days. The cleanest March on record here was 2024 (median AQI 40, 0 days above 100) and the worst was 2019 (median 48, 0 days above 100, peak AQI 78).
- Good: 78.8%
- Moderate: 21.2%
- Unhealthy for Sensitive Groups: 0.0%
- Unhealthy or worse: 0.0%
Improve Indoor Air Quality
Even with good outdoor air in Hartford, indoor PM2.5, dust and allergens build up. A True-HEPA purifier keeps a bedroom or office consistently clean.
Recommended: Levoit Core 400S — True HEPA · CADR ~141 CFM · rooms up to 219 sq ft
As an Amazon Associate, we earn from qualifying purchases.
How is the air in Hartford in March?
Good on a typical day: median AQI 43 across 2019–2025, with 0.0% of March days above AQI 100. Ground-level ozone is the main driver.
- ✓78.8% of March days were Good (AQI 0–50), 21.2% Moderate (51–100).
- ✓0 days of 217 reached AQI 101+; the March peak was 80.
- ✓Best March: 2024; worst March: 2019.
Frequently asked questions
What is the air quality like in Hartford in March?▾
Across 2019–2025, the median daily AQI in Hartford in March was 43 (Good). 78.8% of days were Good, 21.2% Moderate, and 0.0% reached Unhealthy for Sensitive Groups or worse, based on 217 monitored days in EPA's Air Quality System.
Is March a good time for outdoor exercise in Hartford?▾
A typical March day in Hartford sits in the Good range (median AQI 43), so running, cycling and children's outdoor play are fine for everyone on most days; fewer than 1% of March days reached AQI 101+ in 2019–2025.
Which pollutant causes Hartford's March air quality problems?▾
Ground-level ozone set the daily AQI on 71.0% of March days in Hartford. The highest March AQI recorded in 2019–2025 was 80 (Moderate), in 2019.
Hartford March air quality, year by year
Hartford March air quality by year (Hartford-West Hartford-East Hartford, CT, EPA AQS daily AQI)
| Year | Days monitored | Median AQI | Days above 100 | Peak AQI | Main pollutant |
|---|---|---|---|---|---|
| 2019worst | 31 | 48 | 0 | 78 | O3 |
| 2020 | 31 | 41 | 0 | 60 | O3 |
| 2021 | 31 | 43 | 0 | 74 | O3 |
| 2022 | 31 | 44 | 0 | 80 | O3 |
| 2023 | 31 | 44 | 0 | 63 | O3 |
| 2024cleanest | 31 | 40 | 0 | 54 | O3 |
| 2025 | 31 | 44 | 0 | 56 | O3 |
What March air means in Hartford
A typical March day in Hartford sits in the Good range (median AQI 43), so running, cycling and children's outdoor play are fine for everyone on most days; fewer than 1% of March days reached AQI 101+ in 2019–2025.
March's median AQI of 43 is in line with Hartford's whole-year median of 43, so this period is neither a clean nor a dirty stretch for the area. Nationally, the median March AQI across every EPA metro area (102,455 metro-days, 2019–2025) is 42, so Hartford runs in line with the national March norm; 0.0% of its March days topped AQI 100 versus 0.4% nationally (about the same).
March is part of Hartford's spring season (March, April, May); the spring page pools all three months.
Activity-specific thresholds: running, cycling, kids' sports.
Right now in Hartford
The latest EPA AirNow observation puts Hartford's AQI at 36 (PM2.5). The figures above are multi-year month statistics, not today's reading.
View current Hartford air quality →Source: EPA Air Quality System (AQS) pre-generated Daily AQI by CBSA files — daily AQI by CBSA (Hartford-West Hartford-East Hartford, CT), 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.