Durham Air Quality in December

Across 2019–2025, Durham's December air quality had a median AQI of 46 (Good) over 212 monitored days in the Durham-Chapel Hill, NC area. 0.0% of December days (0 of 212) reached Unhealthy for Sensitive Groups or worse, and fine particulate matter (PM2.5) set the daily AQI on 96.7% of days. The cleanest December on record here was 2019 (median AQI 36, 0 days above 100) and the worst was 2023 (median 51, 0 days above 100, peak AQI 73).

46
Median AQI
Good
0.0%
Days above AQI 100
0 of 212 days
61
90th percentile AQI
worst 1 day in 10
74
Peak AQI
Moderate
PM2.5
Main pollutant
96.7% of days
59.9%
Good days
127 of 212
  • Good: 59.9%
  • Moderate: 40.1%
  • Unhealthy for Sensitive Groups: 0.0%
  • Unhealthy or worse: 0.0%

Improve Indoor Air Quality

Even with good outdoor air in Durham, indoor PM2.5, dust and allergens build up. A True-HEPA purifier keeps a bedroom or office consistently clean.

Recommended: Levoit Core 400STrue HEPA · 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 Durham in December?

Good on a typical day: median AQI 46 across 2019–2025, with 0.0% of December days above AQI 100. Fine particulate matter (PM2.5) is the main driver.

  • 59.9% of December days were Good (AQI 0–50), 40.1% Moderate (51–100).
  • 0 days of 212 reached AQI 101+; the December peak was 74.
  • Best December: 2019; worst December: 2023.

Frequently asked questions

What is the air quality like in Durham in December?

Across 2019–2025, the median daily AQI in Durham in December was 46 (Good). 59.9% of days were Good, 40.1% Moderate, and 0.0% reached Unhealthy for Sensitive Groups or worse, based on 212 monitored days in EPA's Air Quality System.

Is December a good time for outdoor exercise in Durham?

A typical December day in Durham sits in the Good range (median AQI 46), 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 Durham's December air quality problems?

Fine particulate matter (PM2.5) set the daily AQI on 96.7% of December days in Durham. The highest December AQI recorded in 2019–2025 was 74 (Moderate), in 2023.

Durham December air quality, year by year

Durham December air quality by year (Durham-Chapel Hill, NC, EPA AQS daily AQI)

YearDays monitoredMedian AQIDays above 100Peak AQIMain pollutant
2019cleanest3136074PM2.5
20203046072PM2.5
20213147069PM2.5
20223139063PM2.5
2023worst2751073PM2.5
20243148065PM2.5
20253141064PM2.5

What December air means in Durham

A typical December day in Durham sits in the Good range (median AQI 46), 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 46 is in line with Durham's whole-year median of 44, so this period is neither a clean nor a dirty stretch for the area. Nationally, the median December AQI across every EPA metro area (95,590 metro-days, 2019–2025) is 39, so Durham 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 Durham's winter season (December, January, February); the winter page pools all three months.

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

Right now in Durham

The latest EPA AirNow observation puts Durham's AQI at 41 (PM2.5). The figures above are multi-year month statistics, not today's reading.

View current Durham air quality →

Source: EPA Air Quality System (AQS) pre-generated Daily AQI by CBSA files — daily AQI by CBSA (Durham-Chapel Hill, NC), 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.