Bad Air Days in Swain County, North Carolina: 2 a Year

2 bad air days a year

Fewer bad air days than most monitored US counties. Ranked 567 of 996 monitored counties, where 1 is worst.

What makes them bad: mostly particles: smoke and dust (94% particle days).

Which months to watch

Most bad days here fall in November. Averaged over 2016 to 2025.

Is a purifier worth it here?

Bad air days are rare here. A standard furnace filter is enough; no purifier needed for outdoor air.
On the odd bad day, check AirNow and keep windows shut.

Better or worse than it was

In 2000 to 2009 this county averaged 4 bad days a year; in 2016 to 2025, 2. The air has improved. The worst recent year was 2016, with 12 bad days on 365 monitored days.

Date	AQI	Main pollutant
2016-11-23	182	PM2.5
2016-11-13	158	PM2.5
2016-11-14	156	PM2.5
2016-11-09	152	PM2.5
2021-03-08	147	PM2.5

An ordinary day in Swain

Across 3,632 monitored days from 2016 to 2025, the air in Swain County rated Good on 74% of them, close to the 72% typical of monitored counties, and Moderate on 25%. The median day sat at AQI 41; one day in ten went above 57.

The pollutant setting the AQI on an ordinary day here:

fine particles (PM2.5)63%2,275 days
ozone37%1,357 days

Swain County by year

Year	Days monitored	Good	Moderate	Over 100	Over 150	Median AQI	Highest AQI
2025*	365	296	69	0	0	37	87
2024	366	305	61	0	0	38	83
2023	365	267	96	2	0	41	115
2022	365	275	90	0	0	43	89
2021	354	261	92	1	0	40	147
2020	362	301	60	1	0	38	119
2019	362	259	103	0	0	42	90
2018	363	255	108	0	0	42	81
2017	365	234	131	0	0	44	71
2016	365	244	109	12	4	44	182
2015	360	244	116	0	0	42	87
2014	359	224	135	0	0	44	84
2013	355	236	119	0	0	43	93
2012	360	210	150	0	0	47	84
2011	362	136	226	0	0	55	82
2010	359	151	208	0	0	53	97

*2025 may be a partial year in EPA's file.

Nearby counties on file

How this is counted

A bad air day is a day the county's daily AQI from EPA AirData went above 100, the level where EPA tells children, older adults and people with asthma or heart disease to cut back outdoors. Monitors do not run every day, so yearly counts are scaled to 365 days. This is the record, not today's air: for that, check AirNow. More on the method in how the county numbers are made, on the AQI 100 line in what counts as a bad air day.