Sterling, Alaska Air Quality
Sterling has a median AQI of 8, earning an air quality grade of A+ — excellent air quality that ranks better than 99% of US cities. Air quality has remained relatively stable over the past decade. Particulate matter (PM2.5) is the primary concern, often linked to vehicle traffic, industrial activity, and wildfire smoke. In 2025, Sterling recorded 20 good air quality days (100% of monitored days).
Population: 6,323 • County: Kenai Peninsula
Current AQI
Quick Facts
| Current AQI | 2 — Good |
| Air Quality Grade | A+ |
| Median AQI (2025) | 8 |
| vs. U.S. Cities | Better than 99% |
| Primary Pollutant | PM2.5 |
| Unhealthy Days/Year | 0 |
| 10-Year Trend | → Stable |
| Data Source | EPA AQS (historical) · AirNow (live) |
Health Recommendation
Air quality is satisfactory, and air pollution poses little or no risk.
It's a great day to be active outside!
5-Day AQI Forecast
Last 90 Days
Current Pollutant Levels
Real-time data from EPA AirNow
Local Air Quality Context
Air quality data for Sterling is sourced from the Port Alberni Elementary monitoring area, located approximately 1280 miles from city center. This EPA-certified station continuously tracks particulate matter (PM2.5), the primary driver of air quality alerts in this area.
Wildfire smoke is a significant factor in Sterling's air quality, with regional fires capable of pushing AQI from Good to Unhealthy within hours during fire season (typically July through October). On smoke-impacted days, staying indoors with windows closed and running an air purifier with a HEPA filter is the most effective protection.
AQI Trend (10 Years)
Air Quality Days by Year
Sterling Median AQI by Year
Annual EPA air quality data for Sterling — median AQI, day-category breakdown, and primary pollutant per year.
| Year | Median AQI | Good Days | Unhealthy Days | Max AQI | Primary Pollutant |
|---|---|---|---|---|---|
| 2025 | 8 | 20 | — | 14 | PM2.5 |
| 2024 | 8 | 122 | — | 42 | PM2.5 |
| 2023 | 10 | 119 | — | 29 | PM2.5 |
| 2022 | 9 | 119 | — | 73 | PM2.5 |
| 2021 | 9 | 121 | — | 41 | PM2.5 |
| 2020 | 10 | 120 | — | 53 | PM2.5 |
| 2019 | 11 | 111 | 1 | 140 | PM2.5 |
| 2018 | 10 | 120 | — | 36 | PM2.5 |
| 2017 | 8 | 67 | — | 30 | PM2.5 |
| 2016 | 9 | 122 | — | 34 | PM2.5 |
Source: EPA Air Quality System (AQS) annual summaries. "Unhealthy Days" includes Unhealthy for Sensitive Groups, Unhealthy, Very Unhealthy, and Hazardous categories.
2025 Air Quality Summary
Primary Pollutant Days (2025)
Days when each pollutant was the primary driver of AQI. Learn about pollutants →
Frequently Asked Questions About Sterling Air Quality
What is the air quality in Sterling today?
The current AQI in Sterling is 2, rated "Good". Air quality is good — outdoor activity is safe for everyone today. Air quality is satisfactory, and air pollution poses little or no risk.
Is air quality in Sterling getting better or worse?
Air quality in Sterling has been stable. The median AQI has dropped 1 points (from 9 in 2016 to 8 in 2025).
What is the most common air pollutant in Sterling?
PM2.5 is the primary air pollutant in Sterling, responsible for 20 days (100% of monitored days) in 2025. Particulate matter originates from vehicle exhaust, wildfires, construction, and industrial activity.
How many unhealthy air days does Sterling have per year?
In 2025, Sterling recorded 100% good air quality days (20 days) out of 20 monitored days. There were 0 Unhealthy for Sensitive Groups days and 0 Unhealthy days (AQI above 100). The highest single-day AQI recorded was 14.
What air quality grade does Sterling receive?
Sterling receives an air quality grade of A+, placing it better than 99% of US cities. This is based on a median AQI of 8 in 2025, with 20 good air quality days. The EPA monitors air quality in this area continuously using certified monitoring stations.
Air Quality Grade
Better than 99% of US cities
Nearby Cities
Get AQI Alerts
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National Rankings
See how Sterling compares to every other US city by air quality.
Best Air Quality Cities →All city rankingsRecommended Air Purifiers for Sterling
Sterling faces elevated PM2.5 from wildfire smoke in addition to year-round traffic and industrial sources. We prioritize True HEPA units with high smoke CADR — essential for rapid air cleaning during smoke events.
Blueair Blue Pure 211+
High performance for large rooms with simple operation.
- ✓Good room size match
- ✓Recommended for your air quality
- ✓High performance
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Other Great Options
Molekule Air Pro
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Honeywell HPA300
Powerful workhorse for large rooms. Built to last.
Coway Airmega AP-1512HH
Best overall value for medium rooms. Excellent performance at an affordable price.
Not sure which air purifier is right for you?
Learn more about different types of air purifiers and how to choose the best one for your needs.
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