Winston-Salem Air Quality in Winter
Across 2019–2025, Winston-Salem's winter (December–February) air quality had a median AQI of 51 (Moderate) over 632 monitored days in the Winston-Salem, NC area. 0.2% of winter days (1 of 632) reached Unhealthy for Sensitive Groups or worse, and fine particulate matter (PM2.5) set the daily AQI on 98.7% of days. The cleanest winter on record here was 2024 (median AQI 42, 0 days above 100) and the worst was 2022 (median 52, 1 day above 100, peak AQI 137).
- Good: 50.0%
- Moderate: 49.8%
- Unhealthy for Sensitive Groups: 0.2%
- Unhealthy or worse: 0.0%
Extra Protection for Winston-Salem Homes
Air quality in Winston-Salem is moderate (AQI 52), with fine particles (PM2.5) the main concern. A True-HEPA purifier gives sensitive groups — kids, seniors and anyone with asthma or allergies — cleaner air indoors on days like today.
Recommended: Coway AP-1512HH Mighty — True HEPA + carbon · CADR ~246 CFM · rooms up to 361 sq ft
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How is the air in Winston-Salem in winter?
Moderate on a typical day: median AQI 51 across 2019–2025, with 0.2% of winter days above AQI 100. Fine particulate matter (PM2.5) is the main driver.
- ✓50.0% of winter days were Good (AQI 0–50), 49.8% Moderate (51–100).
- ✓1 day of 632 reached AQI 101+; the winter peak was 137.
- ✓Cleanest month: January; worst month: February.
Frequently asked questions
What is the air quality like in Winston-Salem in winter?▾
Across 2019–2025, the median daily AQI in Winston-Salem in winter was 51 (Moderate). 50.0% of days were Good, 49.8% Moderate, and 0.2% reached Unhealthy for Sensitive Groups or worse, based on 632 monitored days in EPA's Air Quality System.
Is winter a good time for outdoor exercise in Winston-Salem?▾
A typical winter day in Winston-Salem is Moderate (median AQI 51): outdoor exercise is acceptable for most people, but unusually sensitive individuals should watch for symptoms, and fewer than 1% of winter days reached AQI 101+ — the level at which EPA advises people with asthma, children and older adults to shorten hard outdoor exertion.
Which pollutant causes Winston-Salem's winter air quality problems?▾
Fine particulate matter (PM2.5) set the daily AQI on 98.7% of winter days in Winston-Salem. The highest winter AQI recorded in 2019–2025 was 137 (Unhealthy for Sensitive Groups), in 2022.
Winston-Salem winter air quality, year by year
Winston-Salem winter air quality by year (Winston-Salem, NC, EPA AQS daily AQI)
| Year | Days monitored | Median AQI | Days above 100 | Peak AQI | Main pollutant |
|---|---|---|---|---|---|
| 2019 | 90 | 50 | 0 | 92 | PM2.5 |
| 2020 | 91 | 44 | 0 | 88 | PM2.5 |
| 2021 | 90 | 52 | 0 | 71 | PM2.5 |
| 2022worst | 90 | 52 | 1 | 137 | PM2.5 |
| 2023 | 90 | 51 | 0 | 92 | PM2.5 |
| 2024cleanest | 91 | 42 | 0 | 88 | PM2.5 |
| 2025 | 90 | 54 | 0 | 78 | PM2.5 |
What winter air means in Winston-Salem
A typical winter day in Winston-Salem is Moderate (median AQI 51): outdoor exercise is acceptable for most people, but unusually sensitive individuals should watch for symptoms, and fewer than 1% of winter days reached AQI 101+ — the level at which EPA advises people with asthma, children and older adults to shorten hard outdoor exertion.
Winter's median AQI of 51 is in line with Winston-Salem's whole-year median of 50, so this period is neither a clean nor a dirty stretch for the area. Nationally, the median Winter AQI across every EPA metro area (278,620 metro-days, 2019–2025) is 40, so Winston-Salem runs above the national Winter norm; 0.2% of its Winter days topped AQI 100 versus 0.6% nationally (about the same).
Within the season, January is the cleanest month (median AQI 48, 0.0% of days above 100) and February the worst (median 47, 0.5% above 100).
Activity-specific thresholds: running, cycling, kids' sports.
Right now in Winston-Salem
The latest EPA AirNow observation puts Winston-Salem's AQI at 52 (PM2.5). The figures above are multi-year season statistics, not today's reading.
View current Winston-Salem air quality →Source: EPA Air Quality System (AQS) pre-generated Daily AQI by CBSA files — daily AQI by CBSA (Winston-Salem, 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.