Air quality in Madison County, AL

Includes Huntsville and Madison · EPA monitor readings, 2021 to 2025 · 388,000 people

A few bad days a year
Bad-air days a year
1
day with an AQI over 100

5 bad-air days in 5 years of readings, 2021 to 2025. That's down from about 21 a year in the early 2000s. Madison County has the 2nd most bad-air days of the 14 Alabama counties with monitors.

0days unhealthy for everyoneAQI over 150, a year
46AQI on a typical dayGood: fine for everyone
7bad-air days since 2016Too few to show a season
135worst day since 2016Jul 17, 2023, 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 46 (Good)Worst day 135 (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 Madison County

Bad air is rare here: 7 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
Apr0.1
May0
Jun0.4
Jul0.2
Aug0
Sep0
Oct0
Nov0
Dec0

The worst day since 2016 was July 17, 2023: AQI 135, from fine particles.

What causes it

The 7 bad-air days since 2016 were 6 ozone days (between June 2016 and June 2023) and 1 fine-particle day (on July 17, 2023).

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 ozone days a yearMApril: 0.9 ozone days a yearAMay: 0.1 smoky days a yearMay: 1.0 ozone days a yearMJune: 0.3 smoky days a yearJune: 2.1 ozone days a yearJJuly: 0.2 smoky days a yearJuly: 1.3 ozone days a yearJAugust: 0.2 smoky days a yearAugust: 1.8 ozone days a yearASeptember: 0.1 smoky days a yearSeptember: 1.3 ozone days a yearSOctober: 0.1 ozone days a yearONovember: 0.0 smoky days a yearNDbad daysby month
See the numbers by month
CDC estimated bad-air days a year in each month in Madison County, 2001 to 2022
MonthFine particlesOzone
January00
February00
March00.1
April00.9
May0.11.0
June0.32.1
July0.21.3
August0.21.8
September0.11.3
October00.1
November00
December00

What helps in Madison County

The air here is clean most days: 7 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 2023, with 3 bad-air days.

0204060200036200520102015202020250204060200036201020202025
Unhealthy for sensitive groups (101 to 150)Unhealthy or worse (over 150)
See the numbers by year
Bad-air days each year in Madison County
YearBad-air daysOver 150
2000366
2001160
2002262
2003140
2004120
2005210
2006142
2007252
200890
200910
201040
201140
2012140
201300
201400
201500
201610
201700
201810
201900
202000
202120
202200
202330
202400
202500

Madison County and its neighbors

Bad-air days a year, 2021 to 2025. Alabama counties with monitors averaged about 2 bad-air days a year, weighted by population.

Madison County1
Morgan County<1

Nearest counties with a full report: Etowah County, AL (under 1 bad-air days a year), DeKalb County, AL (under 1 bad-air days a year).

Questions people ask about air in Madison County

How often is the air bad in Madison County?

From 2021 to 2025, monitors in Madison 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 2023, with 3 bad-air days.

What causes bad air in Madison County?

The 7 bad-air days since 2016 were 6 ozone days (between June 2016 and June 2023) and 1 fine-particle day (on July 17, 2023).

Where can I see today's air quality in Madison 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 Madison County is about 46, 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 363 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 Madison 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.