Bad Air Days in Deschutes County, Oregon: 14 a Year

14 bad air days a year

Among the worst tenth of monitored US counties. Ranked 55 of 996 monitored counties, where 1 is worst.

What makes them bad: mostly particles: smoke and dust (100% particle days).

When the bad days come in Deschutes

Most bad days here fall in August and September. Averaged over 2016 to 2025.

What to buy, and what not to

Particles (wildfire smoke, dust) cause enough bad days here to matter. A HEPA purifier sized to your bedroom removes them; run it with windows shut on bad days.
Upgrade the furnace or AC filter to MERV 13 so the whole house is filtered, not just one room.

The record for Deschutes

In 2000 to 2009 this county averaged under 1 bad days a year; in 2016 to 2025, 14. It has got worse. The worst recent year was 2017, with 28 bad days on 365 monitored days.

Date	AQI	Main pollutant
2020-09-11	1099	PM2.5
2020-09-12	867	PM2.5
2020-09-17	740	PM2.5
2020-09-14	701	PM2.5
2020-09-13	560	PM2.5

The air on a normal day

Across 3,612 monitored days from 2016 to 2025, the air in Deschutes County rated Good on 80% of them, more often than the 72% typical of monitored counties, and Moderate on 16%. The median day sat at AQI 27; one day in ten went above 64.

The pollutant setting the AQI on an ordinary day here:

fine particles (PM2.5)98%3,529 days
ozone2%83 days

Deschutes County by year

Year	Days monitored	Good	Moderate	Over 100	Over 150	Median AQI	Highest AQI
2025*	365	326	36	3	1	23	153
2024	366	258	89	19	7	39	176
2023	365	273	66	26	16	28	413
2022	365	282	77	6	4	23	205
2021	365	298	47	20	10	25	403
2020	366	298	54	14	10	23	1099
2019	365	309	51	5	1	26	154
2018	363	273	76	14	5	27	205
2017	365	280	57	28	26	27	479
2016	327	301	26	0	0	29	65
2015	365	295	64	6	1	37	163
2014	365	299	65	1	0	37	113
2013	365	276	89	0	0	39	86
2012	366	281	67	18	17	39	988
2011	365	294	67	4	1	36	176
2010	365	328	37	0	0	34	86

*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.