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

under 1 bad air day a year

Rare: among the cleanest-air counties EPA monitors. Ranked 774 of 996 monitored counties, where 1 is worst.

What makes them bad: mostly particles: smoke and dust (100% particle days).

When the bad days come in Catawba

Most bad days here fall in November and July and June. 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 5 bad days a year; in 2016 to 2025, under 1. The air has improved. The worst recent year was 2023, with 3 bad days on 347 monitored days.

Date	AQI	Main pollutant
2016-11-14	154	PM2.5
2016-11-15	152	PM2.5
2016-11-18	133	PM2.5
2023-07-18	115	PM2.5
2023-06-29	110	PM2.5

The air on a normal day

Across 3,519 monitored days from 2016 to 2025, the air in Catawba County rated Good on 62% of them, less often than the 72% typical of monitored counties, and Moderate on 37%. The median day sat at AQI 44; one day in ten went above 60.

The pollutant setting the AQI on an ordinary day here:

fine particles (PM2.5)100%3,519 days

Every recent year on file

Year	Days monitored	Good	Moderate	Over 100	Over 150	Median AQI	Highest AQI
2025*	347	239	108	0	0	42	88
2024	350	232	118	0	0	42	93
2023	347	212	132	3	0	43	115
2022	355	234	121	0	0	44	81
2021	344	197	147	0	0	46	94
2020	357	247	110	0	0	42	95
2019	361	215	146	0	0	44	74
2018	352	226	126	0	0	43	80
2017	348	203	145	0	0	44	88
2016	358	194	161	3	2	48	154
2015	347	167	180	0	0	52	84
2014	363	213	150	0	0	47	87
2013	364	212	152	0	0	44	75
2012	339	154	185	0	0	51	82
2011	365	139	226	0	0	53	94
2010	363	133	230	0	0	54	90

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

Elsewhere in North Carolina

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.