Bad Air Days in Wake County, North Carolina: 1 a Year

1 bad air day a year

Fewer bad air days than most monitored US counties. Ranked 658 of 996 monitored counties, where 1 is worst.

What makes them bad: mostly particles: smoke and dust (73% particle days).

The bad-air season here

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

What to buy, and what not to

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.

The record for Wake

In 2000 to 2009 this county averaged 35 bad days a year; in 2016 to 2025, 1. The air has improved. The worst recent year was 2023, with 5 bad days on 365 monitored days.

Date	AQI	Main pollutant
2016-11-18	135	PM2.5
2023-06-29	130	PM2.5
2023-07-18	126	PM2.5
2023-06-09	125	PM2.5
2022-06-22	122	Ozone

The air on a normal day

Across 3,648 monitored days from 2016 to 2025, the air in Wake County rated Good on 53% of them, less often than the 72% typical of monitored counties, and Moderate on 47%. The median day sat at AQI 49; one day in ten went above 63.

The pollutant setting the AQI on an ordinary day here:

fine particles (PM2.5)69%2,501 days
ozone31%1,137 days

Wake County by year

Year	Days monitored	Good	Moderate	Over 100	Over 150	Median AQI	Highest AQI
2025*	365	250	115	0	0	43	76
2024	366	226	139	1	0	46	112
2023	365	190	170	5	0	49	130
2022	365	228	136	1	0	46	122
2021	365	199	166	0	0	48	96
2020	365	222	142	1	0	46	101
2019	365	141	224	0	0	53	93
2018	361	152	209	0	0	52	90
2017	365	161	204	0	0	52	100
2016	366	154	209	3	0	53	135
2015	365	142	220	3	0	52	105
2014	365	124	241	0	0	54	100
2013	365	151	214	0	0	52	91
2012	366	170	189	7	1	52	161
2011	365	146	196	23	2	54	156
2010	365	116	240	9	0	56	143

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

North Carolina compared

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.