Cadillac, MI Air Quality

EPA monitor data through 2025 · Updated September 02, 2026 · Methods

In 2025, Cadillac, MI recorded 4 days above an Air Quality Index of 100, the level at which EPA begins warning sensitive groups, out of 365 days with monitoring data. The rest of the year was 314 Good days and 47 Moderate days. Most of the bad days were driven by fine particles. Under the AQI rules that applied before 2013, the same air would have scored 2 days. Since 2000, unhealthy days are 0% higher on a consistent definition.

Unhealthy days, 2025
4
AQI above 100
Same air, pre-2013 rules
2
for comparison with older reports
Good-air days
314
AQI 50 or below
Days monitored
365
full year

Unhealthy days by year, scored two ways

EPA changed what an AQI of 100 means in 2013 and again in 2015, so a count published before those changes is not comparable to one published after. Each panel below applies a single fixed rulebook to every year, so each is internally consistent. Why this matters.

Scored by today's rules

Cadillac, MI: days above AQI 100 by year, current rules 0 6 12 18 24 2000 2005 2010 2015 2020 2025 2000: 5 days 2001: 21 days 2002: 22 days 2003: 17 days 2004: 4 days 2005: 12 days 2006: 11 days 2007: 19 days 2008: 5 days 2009: 2 days 2010: 0 days 2011: 2 days 2012: 18 days 2013: 1 days 2014: 0 days 2015: 2 days 2016: 7 days 2017: 1 days 2018: 2 days 2019: 0 days 2020: 1 days 2021: 1 days 2022: 4 days 2023: 7 days 2024: 0 days 2025: 4 days

Scored by the pre-2013 rules

Cadillac, MI: days above AQI 100 by year, pre-2013 rules 0 6 12 18 24 2000 2005 2010 2015 2020 2025 2000: 2 days 2001: 14 days 2002: 13 days 2003: 8 days 2004: 2 days 2005: 8 days 2006: 6 days 2007: 11 days 2008: 3 days 2009: 1 days 2010: 0 days 2011: 1 days 2012: 7 days 2013: 0 days 2014: 0 days 2015: 0 days 2016: 2 days 2017: 0 days 2018: 1 days 2019: 0 days 2020: 0 days 2021: 0 days 2022: 2 days 2023: 3 days 2024: 0 days 2025: 2 days

What 2025 looked like

Air quality categoryDaysShare of days with an AQI
Good31486%
Moderate4713%
Unhealthy for sensitive groups41%
Unhealthy or worse00%

Median AQI 37 · 90th-percentile AQI 61 · worst day 133. Scored under current rules, out of 365 days with an AQI.

What drove the unhealthy days

Of the 4 days above 100 in 2025, 0 were driven by ozone and 4 by fine particles. The two behave differently. Ozone peaks on hot sunny afternoons; fine particles now spike mainly with wildfire smoke.

The unhealthy days in 2025

Every day the index passed 100, what it reached, and which pollutant drove it. 2 of these 4 would not have counted as unhealthy under the pre-2013 rules.

DatePeak AQIDriven byPre-2013 score
Jul 31133Fine particles 117
Aug 2108Fine particles 96 (not unhealthy)
Aug 3130Fine particles 114
Aug 4113Fine particles 100 (not unhealthy)

Statewide context

Cadillac, MI sits in Michigan.

Days in each air quality category, by year

How many days fell in each AQI category, for every year with an AQI on record. Categories are scored under EPA's current breakpoints. A year with fewer than 300 days is marked, because a short year lowers every count for reasons that have nothing to do with the air.

YearGoodModerate Unhealthy for sensitive groupsUnhealthy or worse Days with an AQI
2000 339214 1365
2001 3073717 4365
2002 2676918 4358
2003 2787016 1365
2004 297624 0363
2005 2678211 1361
2006 287639 2361
2007 2846213 6365
2008 288725 0365
2009 313422 0357
2010 314510 0365
2011 317462 0365
2012 2846418 0366
2013 302621 0365
2014 277880 0365
2015 274892 0365
2016 300597 0366
2017 304601 0365
2018 312512 0365
2019 304610 0365
2020 2471181 0366
2021 2211421 0364
2022 2271344 0365
2023 2041545 2365
2024 326400 0366
2025 314474 0365

Good is AQI 0–50, Moderate 51–100, Unhealthy for sensitive groups 101–150. “Unhealthy or worse” combines the Unhealthy, Very Unhealthy and Hazardous categories, which are shown together because most areas record too few of each to report separately. The four columns sum to the last one by construction. These counts exclude sulphur dioxide, following EPA, which drops SO₂ from county and metro summaries because it is too localized to describe a whole area.

The full series

The same years scored two ways, with the pollutant that drove the days above 100. EPA's files record which pollutant set each day's AQI; they do not attribute days to wildfire smoke, so no column here claims to.

YearUnhealthy days, current rulesOf which ozone Of which fine particlesPre-2013 rulesDays monitored
20005 5 0 2365
200121 21 0 14365
200222 22 0 13358
200317 17 0 8365
20044 4 0 2363
200512 11 1 8361
200611 11 0 6361
200719 19 0 11365
20085 5 0 3365
20092 2 0 1357
20100 0 0 0365
20112 2 0 1365
201218 18 0 7366
20131 1 0 0365
20140 0 0 0365
20152 2 0 0365
20167 7 0 2366
20171 1 0 0365
20182 2 0 1365
20190 0 0 0365
20201 1 0 0366
20211 1 0 0364
20224 4 0 2365
20237 5 2 3365
20240 0 0 0366
20254 0 4 2365

Sources