Air Quality in Kent, Washington — Live
Live readings from PurpleAir sensors across Kent — with free alerts the moment the air turns.
AQI 36 from 5 PurpleAir sensors · Holding steady · data from PurpleAir
As of , the air quality in Kent, Washington is AQI 36 — Good and holding steady — with PM2.5 at 6.5 µg/m³, the median of 5 live PurpleAir sensors reading 32 to 43. Canairy's verdict: Breathe easy.
For scale, that PM2.5 reading is below the World Health Organization's 24-hour guideline of 15 µg/m³. The WHO figure is a daily average and this is a live reading, so read it as a sense of magnitude rather than a formal exceedance — a brief spike and a bad day are not the same thing. More on the WHO guidelines
Pollen today in Kent: weeds pollen is the strongest of the three at a high level, from Google's pollen forecast. Canairy shows the tree, grass and weed forecast beside the air reading on every plan, including the free one.
Free to download · Live data from PurpleAir & public monitors
Live PurpleAir sensor map for Kent and Renton, Auburn, Tukwila, Federal Way. Every dot is a real sensor, color-coded by current air quality.
Sensor by sensor in Kent
The sensors Canairy reads in Kent agree right now — all 5 sit in the Good band, a 11-point spread — so the city-wide number is a fair description of the whole area today.
| From city center | AQI | Category |
|---|---|---|
| 0.5 mi ENE | 32 | Good |
| 2.4 mi SSE | 36 | Good |
| 5.0 mi WNW | 43 | Good |
| 6.1 mi N | 33 | Good |
| 8.1 mi SW | 42 | Good |
Kent sits on the floor of the Green River Valley, and the valley floor is where the freight goes. Interstate 5 runs along the western rim, State Route 167 — the Valley Freeway — runs the length of it, and between them is one of the densest concentrations of warehouses and distribution buildings in the country; the manufacturing and distribution market in Kent and the surrounding area ranks fourth in the United States. When the Washington Department of Ecology drew up its list of sixteen communities overburdened and highly impacted by air pollution, South King County made it, and Kent is named inside the boundary alongside Tukwila, Renton, Des Moines, SeaTac, Auburn, Algona, Pacific and Federal Way. Ecology's own description of the place is short and accurate: a corridor of manufacturing facilities, distribution centers, businesses and rail lines running north-south through the center of the community.
What Canairy does for Kent
A clear verdict
Not just a number — a plain-English call for Kent: open the windows, or keep them shut.
Smoke alerts
A push or text the moment the air crosses your threshold — and again when it clears.
A heads-up before it's bad
Trend alerts catch the air turning, so you can close up the house before the smoke settles in.
Every place you care about
Home, work, the kids' school — across Kent or across the country, on one screen.
What the air in Kent is doing next
| When | AQI | Expected air quality | Main pollutant |
|---|---|---|---|
| Today | 33 | Good | PM2.5 |
| Tomorrow | 53 | Moderate | PM2.5 |
| Sunday | 33 | Good | PM2.5 |
| Monday | 33 | Good | PM2.5 |
| Tuesday | 44 | Good | PM2.5 |
For Thu-Mon (Sep 10-14): Expect GOOD air quality overall through the weekend. Potential for MODERATE to UNHEALTHY FOR SENSITIVE GROUPS air quality in Eastern King and Snohomish Counties starting late Friday night due to wildfire smoke. Rain is expected Saturday afternoon and should help clear out any smoke.
Forecast from EPA AirNow for the Seattle-Bellevue-Kent Valley reporting area. Canairy watches the live sensors against it and tells you when the air actually crosses your threshold, rather than leaving you to check.
The valley floor is one long distribution corridor
Almost everything about the Kent Valley is built around moving goods. The Port of Tacoma is 17 miles away and the Port of Seattle 21; BNSF Railway and Union Pacific both run through the valley with direct access to the national network; Sea-Tac handles over a billion pounds of air cargo a year a few miles to the west. SR-167 and I-5 carry the drayage between all of it. Ecology identified the South King County community not just for short-term fine particle exposure but for cumulative criteria air pollution driven by PM2.5, ozone and nitrogen dioxide in some areas — nitrogen dioxide being the pollutant that tracks most closely with diesel engines and heavy traffic.
It is not warehouses end to end. The same Ecology report notes natural areas and agricultural land along the Green River, and much of Kent outside the valley floor — the East Hill and West Hill above it — is ordinary residential neighborhood. Where you live in Kent relative to the valley and the freeway makes a real difference to what you breathe, which is the argument for watching a sensor near your own address rather than a citywide figure.
What the Kent monitor read before it was switched off
The Puget Sound Clean Air Agency ran a PM2.5 monitor at James and Central until June 2023. Its last full year, 2022, was the worst on the record: a 24-hour 98th-percentile reading of 33.7 micrograms per cubic meter against a federal limit of 35, and an annual mean of 9.25 — over the federal annual standard of 9.0. Its three-year design value settled at 8.3, back under the line. Since the monitor was retired, the nearest regulatory reference point has been Auburn-29th Street, several miles south.
The Auburn numbers show how much of that was smoke rather than traffic. In 2022 the Auburn site's 24-hour 98th percentile was 38.5 micrograms per cubic meter, above the standard — but strip out the days when wildfire smoke pushed the 24-hour average past 35.4, and the figure drops to 26.2. By 2024 it was down to 16.0. Across 2022 to 2024 the South King County community averaged 3.7 days a year with air quality unhealthy for sensitive groups or worse, down from 6.3 days a year over 2020 to 2022. In 2025 Ecology installed three additional low-cost, high-accuracy PM2.5 sensors in the community using Climate Commitment Act funds.
Smoke, and the airport to the west
The honest summary of Kent's air is that traffic and industry set a slightly elevated everyday floor, and smoke causes the days you actually notice. Wildfire smoke does it in late summer, and wood smoke does it in the cold months — the Puget Sound Clean Air Agency issues a Stage 1 burn ban in King County when PM2.5 is predicted to exceed a 24-hour average of 35 micrograms per cubic meter within 48 hours, and those bans typically occur in the fall and winter and usually last a few days.
Sea-Tac is close enough that people ask about it. A two-year University of Washington study, MOV-UP, sampled air within 10 miles of the airport in the direction of aircraft flight and found that communities underneath and downwind of jets landing at Sea-Tac are exposed to a distinct kind of ultrafine particle associated with aircraft rather than roadways, spread over a wider area than road pollution is. The study did not name Kent as one of the affected communities, and ultrafine particles are not what a PurpleAir sensor or the AQI measures — so treat it as a real finding about the airport's surroundings, not a Kent number.
Kent air quality FAQ
What is the air quality in Kent right now?
As of September 11, 2026 at 5:10 AM PDT, the air quality in Kent, Washington is AQI 36 — Good — with PM2.5 at 6.5 µg/m³, the median of 5 live PurpleAir sensors. Open the windows. Great for outdoor activity.
Why is there smoke in Kent today?
In late summer it is almost always wildfire smoke carried in from fires elsewhere, and the monitoring data shows how much difference it makes: at the nearby Auburn site in 2022 the 24-hour 98th-percentile PM2.5 was 38.5 micrograms per cubic meter, but only 26.2 once wildfire-affected days are excluded. In the cold months it is more likely wood smoke from fireplaces and stoves, held near the ground by an inversion over the valley floor — which is when the Puget Sound Clean Air Agency issues its burn bans. If it smells like a campfire and the sky is clear elsewhere, it is usually local wood smoke rather than a distant fire.
Do the warehouses and truck traffic make the air worse?
Ecology identified South King County — Kent included — as overburdened and highly impacted by air pollution partly for cumulative criteria air pollution driven by fine particles, ozone and nitrogen dioxide, and described the community as a corridor of manufacturing facilities, distribution centers, businesses and rail lines running north-south through its center. Nitrogen dioxide is the pollutant most closely tied to diesel engines. What the fine-particle monitors show, though, is that the worst individual days in Kent have been smoke days, not traffic days: the community averaged 3.7 days a year of unhealthy air from 2022 to 2024, down from 6.3 a year over the previous three-year window.
Does Sea-Tac airport affect the air in Kent?
The University of Washington's MOV-UP study sampled within 10 miles of Sea-Tac along aircraft flight paths and found that communities underneath and downwind of landing jets are exposed to a type of ultrafine particle distinctly associated with aircraft, over a larger area than roadway pollution covers. Kent was not named among the affected communities, and ultrafine particles are not captured by the AQI or by consumer sensors, so there is no Kent-specific figure to quote. The airport does sit inside the same South King County community that Ecology flagged, alongside SeaTac, Des Moines and Tukwila.
What the AQI numbers mean
| AQI | Category | What it means for you |
|---|---|---|
| 0–50 | Good | Open the windows. Great for outdoor activity. |
| 51–100 | Moderate | Sensitive groups may want to take it slower outside. |
| 101–150 | Unhealthy for Sensitive Groups | Kids, elderly, and respiratory conditions stay closer to home. |
| 151–200 | Unhealthy | Skip outdoor exercise. Close windows. |
| 201–300 | Very Unhealthy | Limit time outside. N95 if you must go. |
| 301+ | Hazardous | Health emergency. Stay inside, run filtration if you have it. |
Canairy lets you tighten these bands if you’re more sensitive than the EPA default, so an alert can fire before the official category changes. How to read the Air Quality Index
Where these readings come from
The AQI at the top of this page is the median of the 5 curated PurpleAir sensors Canairy tracks in and around Kent, with outliers set aside so that one sensor brought indoors — or parked beside a barbecue — cannot set the number for a whole city. Every sensor behind it is listed above with its distance and bearing from the city center. There is no black box here.
In the app, a place you save resolves the same way first. When no neighborhood sensor is reporting it falls back to the nearest EPA AirNow monitor, and anything modeled rather than measured is labelled a regional estimate rather than passed off as a sensor reading. How low-cost sensors compare to regulatory monitors
About Canairy
Canairy is free to download. The free plan covers one saved place with live readings, a plain-English verdict, and push alerts when the air crosses a threshold you choose. Paid plans add more places, faster refreshes, and SMS alerts. It is built by two parents in Sonoma County, California, who got tired of guessing whether it was safe to send the kids outside. Why we built it
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