Bad Air Days in Stafford County, Virginia: under 1 a Year

under 1 bad air day a year

Rare: among the cleanest-air counties EPA monitors. Ranked 791 of 996 monitored counties, where 1 is worst.

What makes them bad: mostly ozone: summer smog (0% particle days).

When the bad days come in Stafford

Most bad days here fall in June and July and April. 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 28 bad days a year; in 2016 to 2025, under 1. The air has improved. The worst recent year was 2023, with 2 bad days on 365 monitored days.

Date	AQI	Main pollutant
2023-06-02	169	Ozone
2021-07-28	115	Ozone
2018-07-12	112	Ozone
2016-04-19	108	Ozone
2023-06-01	101	Ozone

Most days, not the worst ones

Across 3,119 monitored days from 2016 to 2025, the air in Stafford County rated Good on 95% of them, more often than the 72% typical of monitored counties, and Moderate on 5%. The median day sat at AQI 36; one day in ten went above 48.

The pollutant setting the AQI on an ordinary day here:

ozone98%3,062 days
coarse dust (PM10)2%57 days

Year by year

Year	Days monitored	Good	Moderate	Over 100	Over 150	Median AQI	Highest AQI
2025*	360	347	13	0	0	35	77
2024	362	353	9	0	0	35	90
2023	365	332	31	2	1	37	169
2022	362	351	11	0	0	35	74
2021	358	337	20	1	0	35	115
2020	362	357	5	0	0	32	84
2019	260	244	16	0	0	39	93
2018	264	240	23	1	0	35	112
2017	233	225	8	0	0	38	77
2016	193	162	30	1	0	39	108
2015	214	183	31	0	0	40	97
2014	214	190	23	1	0	41	108
2013	214	195	18	1	0	39	101
2012	214	158	51	5	0	44	140
2011	214	167	41	6	1	41	151
2010	214	137	69	8	2	46	156

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

Virginia 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.