Portland, ME Air Quality in February

Across 2019–2025, Portland's February air quality had a median AQI of 42 (Good) over 198 monitored days in the Portland-South Portland, ME area. 0.5% of February days (1 of 198) reached Unhealthy for Sensitive Groups or worse, and ground-level ozone set the daily AQI on 50.5% of days. The cleanest February on record here was 2023 (median AQI 39, 0 days above 100) and the worst was 2022 (median 39, 1 day above 100, peak AQI 109).

42
Median AQI
Good
0.5%
Days above AQI 100
1 of 198 days
58
90th percentile AQI
worst 1 day in 10
109
Peak AQI
Unhealthy for Sensitive Groups
O3
Main pollutant
50.5% of days
71.7%
Good days
142 of 198
  • Good: 71.7%
  • Moderate: 27.8%
  • Unhealthy for Sensitive Groups: 0.5%
  • Unhealthy or worse: 0.0%

Reduce Indoor Ozone in Portland

Today's main pollutant in Portland is ground-level ozone (AQI 29). Important: standard HEPA filters do NOT remove ozone — only a purifier with a substantial activated-carbon bed adsorbs it. The biggest wins are cutting indoor sources (gas appliances, certain "ionizer" purifiers) and ventilating when outdoor ozone is low (early morning). A high-carbon unit helps with the gases and VOCs that linger indoors.

Recommended: Levoit Core 300True HEPA + activated carbon · CADR ~141 CFM · rooms up to 219 sq ft

Check Price on Amazon →

As an Amazon Associate, we earn from qualifying purchases.

QUICK ANSWER

How is the air in Portland in February?

Good on a typical day: median AQI 42 across 2019–2025, with 0.5% of February days above AQI 100. Ground-level ozone is the main driver.

  • 71.7% of February days were Good (AQI 0–50), 27.8% Moderate (51–100).
  • 1 day of 198 reached AQI 101+; the February peak was 109.
  • Best February: 2023; worst February: 2022.

Frequently asked questions

What is the air quality like in Portland in February?

Across 2019–2025, the median daily AQI in Portland in February was 42 (Good). 71.7% of days were Good, 27.8% Moderate, and 0.5% reached Unhealthy for Sensitive Groups or worse, based on 198 monitored days in EPA's Air Quality System.

Is February a good time for outdoor exercise in Portland?

A typical February day in Portland sits in the Good range (median AQI 42), so running, cycling and children's outdoor play are fine for everyone on most days; fewer than 1% of February days reached AQI 101+ in 2019–2025.

Which pollutant causes Portland's February air quality problems?

Ground-level ozone set the daily AQI on 50.5% of February days in Portland. The highest February AQI recorded in 2019–2025 was 109 (Unhealthy for Sensitive Groups), in 2022.

Portland February air quality, year by year

Portland February air quality by year (Portland-South Portland, ME, EPA AQS daily AQI)

YearDays monitoredMedian AQIDays above 100Peak AQIMain pollutant
20192851081PM2.5
20202952068PM2.5
20212841058O3
2022worst28391109O3
2023cleanest2839072O3
20242941066O3
20252843079O3

What February air means in Portland

A typical February day in Portland sits in the Good range (median AQI 42), so running, cycling and children's outdoor play are fine for everyone on most days; fewer than 1% of February days reached AQI 101+ in 2019–2025.

February's median AQI of 42 is in line with Portland's whole-year median of 40, so this period is neither a clean nor a dirty stretch for the area. Nationally, the median February AQI across every EPA metro area (87,428 metro-days, 2019–2025) is 41, so Portland runs in line with the national February norm; 0.5% of its February days topped AQI 100 versus 0.4% nationally (about the same).

February is part of Portland's winter season (December, January, February); the winter page pools all three months.

Activity-specific thresholds: running, cycling, kids' sports.

Right now in Portland

The latest EPA AirNow observation puts Portland's AQI at 29 (O3). The figures above are multi-year month statistics, not today's reading.

View current Portland air quality →

Source: EPA Air Quality System (AQS) pre-generated Daily AQI by CBSA files — daily AQI by CBSA (Portland-South Portland, ME), 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.