Fargo, ND-MN Air Quality

EPA monitor data through 2025 · Updated August 13, 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. Most of those 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 monitored days
Good276 76%
Moderate75 21%
Unhealthy for sensitive groups4 1%
Unhealthy or worse7 2%

Median AQI 37 · 90th-percentile AQI 71 · worst day 192. Scored under current rules.

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.

The full series

YearUnhealthy days, current rulesPre-2013 rulesDays monitored
200010366
200110365
200200361
200311365
200400366
200511363
200611365
200733365
200800366
200920365
201011365
201100350
201200366
201300355
201410365
201532365
201600366
201700365
201811365
201922364
202000366
20211717365
202210365
2023127365
202422366
20251110362

Sources