Anchorage Air Quality in December
Across 2019–2025, Anchorage's December air quality had a median AQI of 47 (Good) over 217 monitored days in the Anchorage, AK area. 0.0% of December days (0 of 217) reached Unhealthy for Sensitive Groups or worse, and fine particulate matter (PM2.5) set the daily AQI on 94.9% of days. The cleanest December on record here was 2024 (median AQI 41, 0 days above 100) and the worst was 2025 (median 60, 0 days above 100, peak AQI 92).
- Good: 53.5%
- Moderate: 46.5%
- Unhealthy for Sensitive Groups: 0.0%
- Unhealthy or worse: 0.0%
Improve Indoor Air Quality
Even with good outdoor air in Anchorage, 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 Anchorage in December?
Good on a typical day: median AQI 47 across 2019–2025, with 0.0% of December days above AQI 100. Fine particulate matter (PM2.5) is the main driver.
- ✓53.5% of December days were Good (AQI 0–50), 46.5% Moderate (51–100).
- ✓0 days of 217 reached AQI 101+; the December peak was 95.
- ✓Best December: 2024; worst December: 2025.
Frequently asked questions
What is the air quality like in Anchorage in December?▾
Across 2019–2025, the median daily AQI in Anchorage in December was 47 (Good). 53.5% of days were Good, 46.5% Moderate, and 0.0% reached Unhealthy for Sensitive Groups or worse, based on 217 monitored days in EPA's Air Quality System.
Is December a good time for outdoor exercise in Anchorage?▾
A typical December day in Anchorage 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 December days reached AQI 101+ in 2019–2025.
Which pollutant causes Anchorage's December air quality problems?▾
Fine particulate matter (PM2.5) set the daily AQI on 94.9% of December days in Anchorage. The highest December AQI recorded in 2019–2025 was 95 (Moderate), in 2025.
Anchorage December air quality, year by year
Anchorage December air quality by year (Anchorage, AK, EPA AQS daily AQI)
| Year | Days monitored | Median AQI | Days above 100 | Peak AQI | Main pollutant |
|---|---|---|---|---|---|
| 2019 | 31 | 44 | 0 | 91 | PM2.5 |
| 2020 | 31 | 44 | 0 | 89 | PM2.5 |
| 2021 | 31 | 47 | 0 | 81 | PM2.5 |
| 2022 | 31 | 52 | 0 | 89 | PM2.5 |
| 2023 | 31 | 42 | 0 | 68 | PM2.5 |
| 2024cleanest | 31 | 41 | 0 | 95 | PM2.5 |
| 2025worst | 31 | 60 | 0 | 92 | PM2.5 |
What December air means in Anchorage
A typical December day in Anchorage 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 December days reached AQI 101+ in 2019–2025.
December's median AQI of 47 is above Anchorage's whole-year median of 27, making it one of the area's dirtier periods. Nationally, the median December AQI across every EPA metro area (95,590 metro-days, 2019–2025) is 39, so Anchorage runs above the national December norm; 0.0% of its December days topped AQI 100 versus 0.7% nationally (about the same).
December is part of Anchorage's winter season (December, January, February); the winter page pools all three months.
Activity-specific thresholds: running, cycling, kids' sports.
Right now in Anchorage
The latest EPA AirNow observation puts Anchorage's AQI at 18 (PM10). The figures above are multi-year month statistics, not today's reading.
View current Anchorage air quality →Source: EPA Air Quality System (AQS) pre-generated Daily AQI by CBSA files — daily AQI by CBSA (Anchorage, AK), 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.