Air quality in Yakima County, WA

Includes Yakima · EPA monitor readings, 2021 to 2025 (fine particles only) · 257,000 people

Some bad daysOnly particles are measured
Bad-air days a year
9
days with an AQI over 100

About 1 day in 39. That's up from about 4 a year in the early 2000s. Yakima County has the 2nd most bad-air days of the 29 Washington counties with monitors.

4days unhealthy for everyoneAQI over 150, a year
45AQI on a typical dayGood: fine for everyone
Jan, Aug and Sepworst monthsFine particles, the only pollutant measured
743worst day since 2016Sep 14, 2020, fine particles
How to read the AQIThe EPA's air score runs from 0 to 500. Higher is worse. Over 100 counts as a bad-air day.
Typical day 45 (Good)Worst day 743 (Hazardous)
Good0 to 50Moderate51 to 100Sensitive groups101 to 150Unhealthy151 to 200Very unhealthy201 to 300Hazardous301 to 500

When bad air happens in Yakima County

Average bad-air days in each month, from 10 years of daily readings since 2016. Most fall in January, August and September. Only fine particles are measured here.

Jan1.4
Feb0.7
Mar0.2
Apr0
May0
Jun0
Jul0.4
Aug4.9
Sep3.7
Oct0.2
Nov1.1
Dec0.3
0246JanFebMarAprMayJunJulAugSepOctNovDecSMOKE SEASON0246JFMAMJJASONDSMOKE
Fine particles (smoke, soot)Ozone (smog)Bars stack in that order, from the bottom.
See the numbers by month
Average bad-air days a year in each month in Yakima County, from 10 years of daily readings
MonthOzoneFine particlesAll
January01.41.4
February00.70.7
March00.20.2
April000
May000
June000
July00.40.4
August04.94.9
September03.73.7
October00.20.2
November01.11.1
December00.30.3

The worst day since 2016 was September 14, 2020: AQI 743, past the top of the scale at 500, from fine particles.

What causes it

Fine particles are the only pollutant measured here. Most bad days counted here are fine-particle days in summer and fall, the months when wildfire smoke drives particle pollution. Monitors here don't measure ozone, so smog days aren't in these counts.

CDC's model estimates about 0.2 days a year with high ozone at the county's worst spot, 2018 to 2022. See the estimates on the map

CDC estimates by month, 2001 to 2022

The CDC's model counts bad-air days at the county's worst spot, from monitors and satellites. Particles (brown) fill the inside of the ring and ozone (blue) the outside.

January: 0.6 smoky days a yearJFebruary: 0.0 smoky days a yearFMAMJune: 0.0 ozone days a yearJJuly: 0.2 ozone days a yearJAugust: 1.7 smoky days a yearAugust: 0.3 ozone days a yearASeptember: 1.6 smoky days a yearSeptember: 0.1 ozone days a yearSONovember: 0.5 smoky days a yearNDecember: 0.2 smoky days a yearDbad daysby month
See the numbers by month
CDC estimated bad-air days a year in each month in Yakima County, 2001 to 2022
MonthFine particlesOzone
January0.60
February00
March00
April00
May00
June00
July00.2
August1.70.3
September1.60.1
October00
November0.50
December0.20

What helps in Yakima County

Monitors here track fine particles such as smoke, so filtering the air at home helps most. Check the forecast for ozone, which isn't measured here.

Keep one room clean on smoky days

Shut the windows and run an air purifier sized for the room.

Choosing a purifier →

Upgrade the furnace filter

Use MERV 13 if your system can take it, and run the fan on smoky days.

Furnace filters →

Check tomorrow's forecast

AirNow posts an air quality forecast by ZIP code, usually the day before.

AirNow →

For today's reading and tomorrow's forecast, check AirNow by ZIP code. Its fire and smoke map adds smoke plumes.

Purifiers with a verified smoke rating

For a clean room on smoky days. Each has a smoke CADR tested by AHAM's independent program and is certified by California as a mechanical cleaner, so it makes no ozone.

Bedroom or small room

Levoit Vital 100S-P

143 smoke CADR

Everyday
up to 222 sq ft
Heavy smoke
up to 143 sq ft
Filters
about $40 a year

The cheapest unit we found with a verified smoke rating. Enough for a bedroom clean room.

$119.99 at Levoit
Best value for smoke

Levoit Vital 200S-P

250 smoke CADR

Everyday
up to 388 sq ft
Heavy smoke
up to 250 sq ft
Filters
about $50 a year

The most verified smoke cleaning per dollar of any qualifying model: 75% more than the 100S-P for $50 more.

$169.99 at Levoit
Living room or open floor

Levoit Core 600S-P

391 smoke CADR

Everyday
up to 606 sq ft
Heavy smoke
up to 391 sq ft
Filters
$60 to $120 a year

For a big room or a small apartment. Buy the LAP-C601S-WUS version, which CARB lists as mechanical.

$299.99 at Levoit

Why all 3 are Levoit: of the models we checked that pass both tests, these give the most verified smoke cleaning per dollar at each room size. Medify's MA-25 and MA-40 also pass but cost more for the same cleaning.

Ratings from the AHAM Verifide directory and CARB's certified list. Prices from Levoit's site, checked November 7, 2026; they change. We don't earn anything from these links. How to pick a purifier

Every year since 2000

Bad-air days each year. The striped part is days unhealthy for everyone, over AQI 150. The worst recent year was 2021, with 27 bad-air days.

05101520253035200020052010201529202020253051015202530352000201029202020253
Unhealthy for sensitive groups (101 to 150)Unhealthy or worse (over 150)
See the numbers by year
Bad-air days each year in Yakima County
YearBad-air daysOver 150
200030
200140
200220
200320
200493
2005141
2006132
200770
2008151
2009101
201040
2011102
201285
2013184
201492
2015204
2016124
2017298
2018169
2019100
2020159
20212715
202261
202343
202471
202531

Yakima County and its neighbors

Bad-air days a year, 2021 to 2025. Washington counties with monitors averaged about 5 bad-air days a year, weighted by population.

Yakima County9
King County7
Benton County4
Grant County4
Kittitas County3
Pierce County3
Lewis County3

Questions people ask about air in Yakima County

How often is the air bad in Yakima County?

From 2021 to 2025, monitors in Yakima County recorded about 9 bad-air days a year with an AQI above 100, which is unhealthy for sensitive groups or worse. The worst year in that stretch was 2021, with 27 bad-air days.

What causes bad air in Yakima County?

Most bad days counted here are fine-particle days in summer and fall, the months when wildfire smoke drives particle pollution. Bad days cluster in January, August and September. Monitors here don't measure ozone, so smog days aren't in these counts.

Where can I see today's air quality in Yakima County?

AirNow, run by the EPA and its partners, shows the current AQI and tomorrow's forecast for your ZIP code. Its fire and smoke map adds smoke plumes. On a typical day the AQI in Yakima County is about 45, which is good, fine for everyone. Check it most in January, August and September, when bad days here cluster.

About these numbers

Day counts come from the EPA's county air quality summaries, which take the worst reading across a county's monitors each day. Monitors here reported on about 365 days a year from 2021 to 2025. A county is large, and your street can be cleaner or worse. CDC's model, which estimates every county from monitors and satellites, gives the worst spot in Yakima County about 9 high-particle days and almost no high-ozone days a year from 2018 to 2022.

Sources: EPA AirData county AQI summaries (2000 to 2025) and daily county AQI (2016 to 2025); CDC Environmental Public Health Tracking Network modeled PM2.5 and ozone (2001 to 2022). Updated November 8, 2026.