Bad Air Days in Lorain County, Ohio: under 1 a Year

under 1 bad air day a year

Fewer bad air days than most monitored US counties. Ranked 721 of 996 monitored counties, where 1 is worst.

What makes them bad: mostly ozone: summer smog (14% particle days).

Which months to watch

Most bad days here fall in June and July and September. 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 worst days on file

In 2000 to 2009 this county averaged 17 bad days a year; in 2016 to 2025, under 1. The air has improved. The worst recent year was 2016, with 2 bad days on 365 monitored days.

Date	AQI	Main pollutant
2020-07-05	155	PM2.5
2025-07-15	119	Ozone
2016-06-11	115	Ozone
2022-06-22	115	Ozone
2016-09-23	101	Ozone

Most days, not the worst ones

Across 3,087 monitored days from 2016 to 2025, the air in Lorain County rated Good on 80% of them, more often than the 72% typical of monitored counties, and Moderate on 20%. The median day sat at AQI 39; one day in ten went above 55.

The pollutant setting the AQI on an ordinary day here:

ozone62%1,910 days
fine particles (PM2.5)38%1,176 days

Lorain County by year

Year	Days monitored	Good	Moderate	Over 100	Over 150	Median AQI	Highest AQI
2025*	237	207	29	1	0	39	119
2024	245	216	29	0	0	39	74
2023	243	221	22	0	0	37	90
2022	243	228	14	1	0	35	115
2021	304	208	96	0	0	41	90
2020	358	289	68	1	1	39	155
2019	362	260	102	0	0	41	75
2018	365	255	109	1	0	41	101
2017	365	298	66	1	0	38	101
2016	365	295	68	2	0	37	115
2015	364	288	76	0	0	37	93
2014	363	266	97	0	0	39	93
2013	362	243	119	0	0	40	94
2012	364	220	130	14	2	46	159
2011	355	203	145	7	0	46	136
2010	361	142	207	12	0	55	140

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

Ohio 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.