Montgomery County, Tennessee air quality history

Daily Air Quality Index summaries from EPA monitors in Montgomery, Tennessee, 1982–2025.

84%

Good days in 2025

Median daily AQI, 2025

Days above 100 in 2025

358

Days with an AQI in 2025 (of 365)

In 2025, EPA reported a daily Air Quality Index (AQI) for Montgomery, Tennessee on 358 days. 300 of those days (84%) were in the Good range, and the median daily AQI was 32. That median is lower than the typical monitored county in Tennessee (median 39 across 23 counties), and lower than the typical monitored U.S. county (40). The main pollutant was fine particles (PM2.5) on 358 days. Across the years with fuller monitoring, the share of Good days fell: an average of 97% in 1989–1996 versus 82% in 2023–2025.

Years with fewer than 120 monitored days (2002, 2008, 2009, 2010, 2011, 2012…) are shown in the table but left out of comparisons and trend statements.

How the days broke down each year

Each bar is one year. The colored segments show the share of monitored days that fell in each AQI category.

Good
Moderate
Unhealthy for Sensitive Groups
Unhealthy
Very Unhealthy
Hazardous

Typical and high-end AQI over time

The median is the middle day of the year. The 90th percentile is the level that only the highest 10% of days exceeded.

Median daily AQI
90th-percentile daily AQI

Main pollutant by day, 2025

On each monitored day, the AQI reflects whichever measured pollutant had the highest index. This counts how many days each pollutant set the AQI. A pollutant that was not measured here cannot appear.

Pollutant	Days as main pollutant	Share of monitored days
Fine particles (PM2.5)	358	100%

Year-by-year data

Annual AQI summary by year
Year	Days with AQI	Good	Moderate	Unhealthy for Sensitive Groups	Unhealthy	Median AQI	90th pct.	Max AQI	Main pollutant
2025	358	300	57	1	0	32	54	130	PM2.5
2024	361	302	59	0	0	32	52	79	PM2.5
2023	351	271	79	1	0	36	58	105	PM2.5
2022	359	280	79	0	0	36	55	87	PM2.5
2021	359	279	79	1	0	33	59	138	PM2.5
2020	359	288	69	2	0	35	54	116	PM2.5
2019	362	278	84	0	0	35	55	67	PM2.5
2018	354	241	113	0	0	40	58	80	PM2.5
2017	341	227	114	0	0	41	57	72	PM2.5
2016	308	218	90	0	0	42	56	68	PM2.5
2015	356	225	131	0	0	44	59	74	PM2.5
2014	344	202	142	0	0	47	62	85	PM2.5
2013	355	206	149	0	0	46	61	80	PM2.5
2012	62	28	34	0	0	52	65	78	PM2.5
2011	62	26	36	0	0	55	72	84	PM2.5
2010	62	21	41	0	0	55	65	96	PM2.5
2009	62	29	33	0	0	51	64	81	PM2.5
2008	61	20	41	0	0	56	71	91	PM2.5
2007	345	111	227	7	0	56	79	143	PM2.5
2006	219	99	117	3	0	54	75	113	PM2.5
2005	320	163	141	15	1	50	90	154	Ozone
2004	121	45	76	0	0	54	73	90	PM2.5
2003	122	50	70	2	0	53	82	108	PM2.5
2002	116	47	69	0	0	53	73	98	PM2.5
2001	177	92	85	0	0	48	72	93	PM2.5
2000	300	132	132	31	5	54	108	174	Ozone
1999	122	26	93	3	0	59	86	119	PM2.5
1998	69	69	0	0	0	21	37	44	PM10
1997	73	73	0	0	0	19	32	46	PM10
1996	125	122	3	0	0	20	38	58	PM10
1995	362	356	6	0	0	20	32	58	NO2
1994	51	50	1	0	0	19	31	51	PM10
1989	144	137	7	0	0	13	40	56	CO
1982	68	68	0	0	0	7	17	22	CO

What this data can and can’t tell you

It is a county-level summary. EPA reports one AQI per day for the county, based on the monitors operating there. Air at a particular street, school or home can differ, especially near roads, industry or wildfire smoke.

It is not a health assessment. The AQI is EPA’s scale for communicating daily air quality. A county’s history can’t tell you what the health risk is for any particular person. For daily conditions and health guidance, see AirNow.

Rules change over time. EPA has revised AQI breakpoints, most recently for fine particles in 2024, so some year-to-year change can reflect the scale rather than the air.

Counties in Tennessee with a similar median AQI in 2025

All monitored counties in Tennessee

Source: U.S. EPA AirData, “Annual AQI by County” files for 1982–2025 (EPA download page). EPA file dates: 2026-06-26. Imported into EnviroNearby November 5, 2026. How we use this data · Report a problem