Bad Air Days in Essex County, New York: 2 a Year

2 bad air days a year

About the middle of monitored US counties. Ranked 478 of 996 monitored counties, where 1 is worst.

What makes them bad: a mix of particles and ozone (50% particle days).

Which months to watch

Most bad days here fall in June and July and April and August. 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 16 bad days a year; in 2016 to 2025, 2. The air has improved. The worst recent year was 2023, with 10 bad days on 365 monitored days.

Date	AQI	Main pollutant
2023-06-06	161	PM2.5
2025-07-26	159	PM2.5
2023-06-25	154	PM2.5
2023-07-01	131	PM2.5
2025-06-07	131	PM2.5

Most days, not the worst ones

Across 3,651 monitored days from 2016 to 2025, the air in Essex County rated Good on 87% of them, more often than the 72% typical of monitored counties, and Moderate on 12%. The median day sat at AQI 41; one day in ten went above 55.

The pollutant setting the AQI on an ordinary day here:

ozone94%3,421 days
fine particles (PM2.5)6%230 days

Every recent year on file

Year	Days monitored	Good	Moderate	Over 100	Over 150	Median AQI	Highest AQI
2025*	365	306	54	5	1	41	159
2024	366	310	56	0	0	41	80
2023	365	296	59	10	2	42	161
2022	365	342	21	2	0	41	115
2021	365	310	54	1	0	40	101
2020	365	344	21	0	0	39	80
2019	364	327	37	0	0	42	80
2018	365	317	46	2	0	41	108
2017	365	308	57	0	0	40	90
2016	366	330	34	2	0	39	112
2015	365	323	42	0	0	40	100
2014	365	343	21	1	0	39	101
2013	365	317	48	0	0	40	100
2012	366	296	62	8	2	41	154
2011	364	307	57	0	0	41	93
2010	365	284	72	9	1	42	162

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

Nearby counties on file

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.