Fargo, ND-MN Air Quality

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

In 2025, Fargo, ND-MN recorded 11 days above an Air Quality Index of 100, the level at which EPA begins warning sensitive groups, out of 362 days with monitoring data. The rest of the year was 276 Good days and 75 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 10 days.

Unhealthy days, 2025
11
AQI above 100
Same air, pre-2013 rules
10
for comparison with older reports
Good-air days
276
AQI 50 or below
Days monitored
362
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

Fargo, ND-MN: days above AQI 100 by year, current rules 0 4 8 12 16 2000 2005 2010 2015 2020 2025 2000: 1 days 2001: 1 days 2002: 0 days 2003: 1 days 2004: 0 days 2005: 1 days 2006: 1 days 2007: 3 days 2008: 0 days 2009: 2 days 2010: 1 days 2011: 0 days 2012: 0 days 2013: 0 days 2014: 1 days 2015: 3 days 2016: 0 days 2017: 0 days 2018: 1 days 2019: 2 days 2020: 0 days 2021: 17 days 2022: 1 days 2023: 12 days 2024: 2 days 2025: 11 days

Scored by the pre-2013 rules

Fargo, ND-MN: days above AQI 100 by year, pre-2013 rules 0 4 8 12 16 2000 2005 2010 2015 2020 2025 2000: 0 days 2001: 0 days 2002: 0 days 2003: 1 days 2004: 0 days 2005: 1 days 2006: 1 days 2007: 3 days 2008: 0 days 2009: 0 days 2010: 1 days 2011: 0 days 2012: 0 days 2013: 0 days 2014: 0 days 2015: 2 days 2016: 0 days 2017: 0 days 2018: 1 days 2019: 2 days 2020: 0 days 2021: 17 days 2022: 0 days 2023: 7 days 2024: 2 days 2025: 10 days

What 2025 looked like

Air quality categoryDaysShare of days with an AQI
Good27676%
Moderate7521%
Unhealthy for sensitive groups41%
Unhealthy or worse72%

Median AQI 37 · 90th-percentile AQI 71 · worst day 192. Scored under current rules, out of 362 days with an AQI.

What drove the unhealthy days

Of the 11 days above 100 in 2025, 1 were driven by ozone and 10 by fine particles. The two behave differently. Ozone peaks on hot sunny afternoons; fine particles now spike mainly with wildfire smoke. In the eastern United States, ozone has stopped responding to emission cuts: nitrogen oxide emissions kept falling after 2014 and ambient ozone barely moved.

The unhealthy days in 2025

Every day the index passed 100, what it reached, and which pollutant drove it. 1 of these 11 would not have counted as unhealthy under the pre-2013 rules.

DatePeak AQIDriven byPre-2013 score
May 13105Ozone 90 (not unhealthy)
Jun 1192Fine particles 179
Jun 2168Fine particles 159
Jun 11127Fine particles 112
Jul 11166Fine particles 158
Jul 12178Fine particles 167
Jul 30153Fine particles 135
Jul 31160Fine particles 152
Aug 1147Fine particles 128
Aug 2130Fine particles 114
Aug 11152Fine particles 134

Statewide context

Fargo, ND-MN sits in North Dakota, Minnesota.

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 321441 0366
2001 301631 0365
2002 311500 0361
2003 292721 0365
2004 321450 0366
2005 306560 1363
2006 297671 0365
2007 311511 2365
2008 313530 0366
2009 315482 0365
2010 2251391 0365
2011 253970 0350
2012 2411250 0366
2013 273820 0355
2014 285791 0365
2015 2351273 0365
2016 2631030 0366
2017 2351300 0365
2018 277871 0365
2019 302601 1364
2020 306600 0366
2021 2291198 9365
2022 285791 0365
2023 18016610 2358
2024 288761 1366
2025 276754 7362

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
20001 1 0 0366
20011 0 1 0365
20020 0 0 0361
20031 0 1 1365
20040 0 0 0366
20051 0 1 1363
20061 0 1 1365
20073 0 3 3365
20080 0 0 0366
20092 0 2 0365
20101 0 1 1365
20110 0 0 0350
20120 0 0 0366
20130 0 0 0355
20141 0 1 0365
20153 0 3 2365
20160 0 0 0366
20170 0 0 0365
20181 0 1 1365
20192 0 2 2364
20200 0 0 0366
202117 1 16 17365
20221 0 1 0365
202312 2 10 7365
20242 0 2 2366
202511 1 10 10362

Sources