Air quality in Montgomery County, TN

EPA monitor readings, 2021 to 2025 (fine particles only) · 220,000 people

Clean most daysOnly particles are measured
Bad-air days a year
<1
day with an AQI over 100

3 bad-air days in 5 years of readings, 2021 to 2025. Montgomery County is tied with 3 other Tennessee counties for the 9th most bad-air days of the 23 with monitors.

0days unhealthy for everyoneAQI over 150, a year
34AQI on a typical dayGood: fine for everyone
5bad-air days since 2016Too few to show a season
138worst day since 2016Jul 5, 2021, fine particles
How to read the AQIThe EPA's air score runs from 0 to 500. Higher is worse. Over 100 counts as a bad-air day.
Typical day 34 (Good)Worst day 138 (Unhealthy for sensitive groups)
Good0 to 50Moderate51 to 100Sensitive groups101 to 150Unhealthy151 to 200Very unhealthy201 to 300Hazardous301 to 500

Bad-air days by month in Montgomery County

Bad air is rare here: 5 bad-air days in 10 years of daily readings since 2016, too few to show a season. Each tile is the average for that month.

Jan0
Feb0
Mar0
Apr0
May0
Jun0.1
Jul0.4
Aug0
Sep0
Oct0
Nov0
Dec0

The worst day since 2016 was July 5, 2021: AQI 138, from fine particles (fireworks are a common cause).

What causes it

Fine particles are the only pollutant measured here. The 5 bad-air days since 2016 were all fine-particle days, between June 2020 and July 2025. 3 of them fell on the Fourth of July, when fireworks smoke can push fine particles up. Monitors here don't measure ozone, so smog days aren't in these counts.

CDC's model estimates about 0.0 days a year with high ozone at the county's worst spot, 2018 to 2022. See the estimates on the map

CDC estimates by month, 2001 to 2022

The CDC's model counts bad-air days at the county's worst spot, from monitors and satellites. Particles (brown) fill the inside of the ring and ozone (blue) the outside.

JFMarch: 0.1 smoky days a yearMarch: 0.1 ozone days a yearMApril: 0.8 ozone days a yearAMay: 0.0 smoky days a yearMay: 0.9 ozone days a yearMJune: 0.1 smoky days a yearJune: 2.0 ozone days a yearJJuly: 0.1 smoky days a yearJuly: 1.0 ozone days a yearJAugust: 0.2 smoky days a yearAugust: 2.0 ozone days a yearASeptember: 0.3 smoky days a yearSeptember: 0.8 ozone days a yearSOctober: 0.1 ozone days a yearONDbad daysby month
See the numbers by month
CDC estimated bad-air days a year in each month in Montgomery County, 2001 to 2022
MonthFine particlesOzone
January00
February00
March0.10.1
April00.8
May00.9
June0.12.0
July0.11.0
August0.22.0
September0.30.8
October00.1
November00
December00

What helps in Montgomery County

The air here is clean most days: 5 bad-air days in 10 years of daily readings. Wildfire smoke can still drift in from far away, so it's worth being ready.

Check tomorrow's forecast

AirNow posts an air quality forecast by ZIP code, usually the day before.

AirNow →

Keep a cheap backup

A box fan with a MERV 13 filter clamped to it cleans a room in a pinch.

Build one →

Keep one room clean on smoky days

Shut the windows and run an air purifier sized for the room.

Choosing a purifier →

For today's reading and tomorrow's forecast, check AirNow by ZIP code. Its fire and smoke map adds smoke plumes.

Smoky days are rare here, so a purifier is optional. If you want one for wildfire season anyway, see the 3 models we'd buy, each with a verified smoke rating.

Every year since 2000

Bad-air days each year. The striped part is days unhealthy for everyone, over AQI 150. The worst recent year was 2021, with 1 bad-air day.

0204060200036200520152020202510204060200036202020251
Unhealthy for sensitive groups (101 to 150)Unhealthy or worse (over 150)
See the numbers by year
Bad-air days each year in Montgomery County
YearBad-air daysOver 150
2000365
2005161
200630
200770
201300
201400
201500
201600
201700
201800
201900
202020
202110
202200
202310
202400
202510

Montgomery County and its neighbors

Bad-air days a year, 2021 to 2025. Tennessee counties with monitors averaged about 3 bad-air days a year, weighted by population.

Christian County1
Montgomery County<1

Nearest counties with a full report: Davidson County, TN (3 bad-air days a year), Williamson County, TN (under 1 bad-air day a year).

Questions people ask about air in Montgomery County

How often is the air bad in Montgomery County?

From 2021 to 2025, monitors in Montgomery County recorded about 1 bad-air day a year with an AQI above 100, which is unhealthy for sensitive groups or worse. The worst year in that stretch was 2021, with 1 bad-air day.

What causes bad air in Montgomery County?

The 5 bad-air days since 2016 were all fine-particle days, between June 2020 and July 2025. 3 of them fell on the Fourth of July, when fireworks smoke can push fine particles up. Monitors here don't measure ozone, so smog days aren't in these counts.

Where can I see today's air quality in Montgomery County?

AirNow, run by the EPA and its partners, shows the current AQI and tomorrow's forecast for your ZIP code. Its fire and smoke map adds smoke plumes. On a typical day the AQI in Montgomery County is about 34, which is good, fine for everyone. Bad days are rare here, so check it when wildfire smoke is in the news.

About these numbers

Day counts come from the EPA's county air quality summaries, which take the worst reading across a county's monitors each day. Monitors here reported on about 358 days a year from 2021 to 2025. A county is large, and your street can be cleaner or worse. CDC's model, which estimates every county from monitors and satellites, gives the worst spot in Montgomery County almost no high-particle days and almost no high-ozone days a year from 2018 to 2022.

Sources: EPA AirData county AQI summaries (2000 to 2025) and daily county AQI (2016 to 2025); CDC Environmental Public Health Tracking Network modeled PM2.5 and ozone (2001 to 2022). Updated November 8, 2026.