Bad Air Days in Carter County, Kentucky: under 1 a Year

under 1 bad air days a year

Rare: among the cleanest-air counties EPA monitors. Ranked 864 of 996 monitored counties, where 1 is worst.

What makes them bad: mostly particles: smoke and dust (100% 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 worst days on file

In 2000 to 2009 this county averaged 13 bad days a year; in 2016 to 2025, under 1. The air has improved. The worst recent year was 2023, with 2 bad days on 364 monitored days.

Date	AQI	Main pollutant
2023-06-28	153	PM2.5
2023-06-29	132	PM2.5
2016-11-08	103	PM2.5
2023-07-17	98	PM2.5
2016-04-19	97	Ozone

The air on a normal day

Across 3,150 monitored days from 2016 to 2025, the air in Carter County rated Good on 88% of them, more often than the 72% typical of monitored counties, and Moderate on 12%. The median day sat at AQI 37; one day in ten went above 51.

The pollutant setting the AQI on an ordinary day here:

ozone59%1,852 days
fine particles (PM2.5)41%1,292 days

Every recent year on file

Year	Days monitored	Good	Moderate	Over 100	Over 150	Median AQI	Highest AQI
2025*	364	324	40	0	0	36	82
2024	360	321	39	0	0	37	62
2023	364	284	78	2	1	40	153
2022	361	293	68	0	0	39	71
2021	279	252	27	0	0	35	86
2020	285	273	12	0	0	33	64
2019	285	266	19	0	0	37	67
2018	281	248	33	0	0	35	80
2017	285	261	24	0	0	38	77
2016	286	253	32	1	0	38	103
2015	265	227	38	0	0	38	74
2014	283	226	57	0	0	39	90
2013	284	227	57	0	0	41	97
2012	285	208	72	5	0	43	150
2011	277	204	72	1	1	43	157
2010	283	172	105	6	0	47	115

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

Kentucky 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.