Bad Air Days in Scott County, Minnesota: 3 a Year

3 bad air days a year

About the middle of monitored US counties. Ranked 386 of 996 monitored counties, where 1 is worst.

What makes them bad: a mix of particles and ozone (59% particle days).

The bad-air season here

Most bad days here fall in June and May and July. Averaged over 2016 to 2025.

What actually helps here

Bad air days are rare here. A standard furnace filter is enough; no purifier needed for outdoor air.
On the odd bad day, check AirNow and keep windows shut.

The record for Scott

In 2000 to 2009 this county averaged 4 bad days a year; in 2016 to 2025, 3. Not much has changed. The worst recent year was 2023, with 17 bad days on 365 monitored days.

Date	AQI	Main pollutant
2023-06-14	179	PM2.5
2025-06-03	172	PM2.5
2025-07-12	167	PM2.5
2025-07-31	160	PM2.5
2025-08-01	160	PM2.5

An ordinary day in Scott

Across 3,623 monitored days from 2016 to 2025, the air in Scott County rated Good on 77% of them, more often than the 72% typical of monitored counties, and Moderate on 23%. The median day sat at AQI 39; one day in ten went above 60.

The pollutant setting the AQI on an ordinary day here:

ozone59%2,135 days
fine particles (PM2.5)41%1,488 days

Every recent year on file

Year	Days monitored	Good	Moderate	Over 100	Over 150	Median AQI	Highest AQI
2025*	365	266	91	8	4	38	172
2024	366	258	107	1	0	42	138
2023	365	173	175	17	5	51	179
2022	365	282	83	0	0	42	89
2021	351	263	88	0	0	39	98
2020	365	307	57	1	0	35	121
2019	365	273	92	0	0	38	93
2018	357	306	49	2	0	37	112
2017	363	321	42	0	0	34	87
2016	361	328	33	0	0	32	93
2015	364	331	33	0	0	34	90
2014	306	255	51	0	0	36	90
2013	261	197	63	1	0	42	108
2012	267	190	75	2	0	42	119
2011	252	214	37	1	0	39	101
2010	242	189	51	2	0	38	120

*2025 may be a partial year in EPA's file.

Minnesota compared

How this is counted

A bad air day is a day the county's daily AQI from EPA AirData went above 100, the level where EPA tells children, older adults and people with asthma or heart disease to cut back outdoors. Monitors do not run every day, so yearly counts are scaled to 365 days. This is the record, not today's air: for that, check AirNow. More on the method in how the county numbers are made, on the AQI 100 line in what counts as a bad air day, and on why a purifier does not touch ozone in smoke vs ozone.