Bad Air Days in Cumberland County, New Jersey: 2 a Year

2 bad air days a year

Fewer bad air days than most monitored US counties. Ranked 582 of 996 monitored counties, where 1 is worst.

What makes them bad: mostly ozone: summer smog (40% particle days).

When the bad days come in Cumberland

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

Is a purifier worth it 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.

Better or worse than it was

In 2000 to 2009 this county averaged 21 bad days a year; in 2016 to 2025, 2. The air has improved. The worst recent year was 2023, with 5 bad days on 361 monitored days.

Date	AQI	Main pollutant
2023-06-08	203	PM2.5
2023-06-07	187	PM2.5
2023-06-01	142	PM2.5
2023-06-29	141	PM2.5
2016-05-25	136	Ozone

The air on a normal day

Across 3,629 monitored days from 2016 to 2025, the air in Cumberland County rated Good on 74% of them, close to the 72% typical of monitored counties, and Moderate on 26%. The median day sat at AQI 42; one day in ten went above 58.

The pollutant setting the AQI on an ordinary day here:

ozone53%1,934 days
fine particles (PM2.5)45%1,644 days
nitrogen dioxide1%51 days

Every recent year on file

Year	Days monitored	Good	Moderate	Over 100	Over 150	Median AQI	Highest AQI
2025*	362	276	83	3	0	40	123
2024	359	290	68	1	0	39	112
2023	361	262	94	5	2	43	203
2022	362	308	54	0	0	38	84
2021	364	291	71	2	0	39	112
2020	365	251	114	0	0	44	72
2019	361	254	104	3	0	44	105
2018	365	241	124	0	0	43	93
2017	364	254	110	0	0	42	84
2016	366	245	120	1	0	44	136
2015	362	317	43	2	0	33	108
2014	364	342	21	1	0	35	101
2013	303	285	18	0	0	34	90
2012	338	224	98	16	3	42	164
2011	359	232	125	2	0	43	122
2010	363	236	116	11	0	43	143

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

Elsewhere in New Jersey

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.