Air Quality in Dover, Delaware — Live
Live readings from PurpleAir sensors across Dover — with free alerts when ozone or drifting smoke push the air quality down.
AQI 11 from 2 PurpleAir sensors · Trending down · data from PurpleAir
As of , the air quality in Dover, Delaware is AQI 11 — Good and falling — with PM2.5 at 2.0 µg/m³, the median of 2 live PurpleAir sensors reading 9 to 13. 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 Dover: 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 Dover and Camden, Wyoming, Smyrna, Cheswold. Every dot is a real sensor, color-coded by current air quality.
Sensor by sensor in Dover
The sensors Canairy reads in Dover agree right now — all 2 sit in the Good band, a 4-point spread — so the city-wide number is a fair description of the whole area today.
| From city center | AQI | Category |
|---|---|---|
| City center | 13 | Good |
| 4.2 mi E | 9 | Good |
Most days in Dover the air is unremarkable in the best way — this stretch of the mid-Atlantic doesn't have a wildfire season, and the Delaware Bay's sea breeze usually keeps things from turning oppressive. The real story here is ozone: Kent County sits inside the Philadelphia-Reading-Camden metro area's summer smog problem, and hot, still, humid afternoons can push the air unhealthy for sensitive groups well before anyone notices anything in the sky. In 2023, smoke drifting down from Canada's record wildfire season also broke the county's 13-year streak of top marks for particle pollution — proof that "no local fires" doesn't mean the air is always fine to ignore.
What Canairy does for Dover
A clear verdict
Not just a number — a plain-English call for Dover: 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 Dover or across the country, on one screen.
What the air in Dover is doing next
| When | AQI | Expected air quality | Main pollutant |
|---|---|---|---|
| Today | 42 | Good | ozone |
| Tomorrow | 48 | Good | ozone |
Monday, September 14: Moderate northerly winds will disperse pollutants and keep the lower levels of the atmosphere well mixed as a cold front departs to the south. Therefore, despite increasing sunshine aiding ozone production during the afternoon, AQI levels are anticipated to be Good for ozone and PM2.5. Tuesday, mostly sunny skies throughout the day will allow ozone development to increase. However, light easterly to southeasterly winds will recirculate a clean air mass across the state. As a result, Good AQI levels are anticipated for ozone and PM2.5. Wednesday, a ridge of high pressure aloft will hinder atmospheric mixing. Furthermore, mostly sunny skies and highs in the low 80s will aid ozone formation, while light south-southwesterly winds limit dispersion. However, pollutant carryover from the previous days will be low. Therefore, high-Good AQI levels are anticipated for ozone and PM2.5.
Forecast from EPA AirNow for the Kent County 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.
Dover's air problem is summer ozone, not fire smoke
Kent County earned a C grade for ozone in the American Lung Association's 2026 State of the Air report, holding steady after slipping from a B the year before. The county sits inside the Philadelphia-Reading-Camden, PA-NJ-DE-MD metro area, which the same report ranked 43rd worst in the nation for ozone smog — a region that earns straight F's most years. Dover's flat coastal-plain geography doesn't create ozone on its own; it just does little to clear out what forms locally or drifts down the I-95 corridor from Philadelphia, Wilmington, and Baltimore on hot, sunny, windless days.
Ozone forms when sunlight cooks vehicle and industrial exhaust, and Dover's summers give it plenty of fuel: the city averages around 25 days a year at or above 90°F, with the kind of still, humid air that lets smog build through the afternoon instead of blowing through. That's the pattern to watch from roughly May through September — a clear, hot midday can turn into an unhealthy-for-sensitive-groups afternoon well before the air looks any different.
The 2023 Canadian wildfire smoke broke a 13-year clean streak
For 13 straight years, Kent County posted a top grade for short-term particle pollution in the American Lung Association's annual reports. That streak ended with the smoke that drifted down from Canada's record 2023 wildfire season — the same haze that turned skies orange as far south as Philadelphia and Washington, D.C. — which pushed the county's particle-pollution grade down to a D, according to reporting on the American Lung Association's findings.
It was an unusual year, not a new normal: Dover doesn't have a local wildfire season, and most years its particle pollution stays low. But the 2023 episode showed that smoke from fires hundreds of miles north can still reach Delaware's coastal plain when the wind sets up right — exactly the kind of event a live sensor catches well before the sky looks obviously smoky.
Route 13 and Dover Air Force Base add to the everyday mix
Dover doesn't have the refineries or ports that drive air quality in some bigger cities, but it isn't pollution-free at street level either. U.S. Route 13 — the old DuPont Highway — runs directly through the city as a major freight corridor, with Delaware Route 1 and Route 8 adding more through-traffic on the edges. Dover Air Force Base, one of the largest air bases on the East Coast and home to the Air Force's C-5M and C-17 fleets, sits along the city's southeast side, and flight operations are a visible, audible part of daily life here.
None of that rivals what a summer ozone day or a smoke-transport event does to the numbers, but it means Dover's air quality isn't just a story about weather fronts moving through — it's also about what's idling on Route 13 or taking off from the base on a still afternoon, particularly for anyone who lives close to the highway or the flight path.
Dover air quality FAQ
What is the air quality in Dover right now?
As of September 14, 2026 at 6:28 PM EDT, the air quality in Dover, Delaware is AQI 11 — Good — with PM2.5 at 2.0 µg/m³, the median of 2 live PurpleAir sensors. Open the windows. Great for outdoor activity.
Why did Dover's air quality grade drop in recent years?
Kent County's ozone grade slipped from a B to a C, and its particle-pollution grade fell all the way to a D after 13 straight years of A's, according to the American Lung Association's State of the Air reports. The ozone decline reflects the broader Philadelphia-Reading-Camden metro area's summer smog, while the particle-pollution drop traces largely to smoke that drifted down from Canada's severe 2023 wildfire season.
Does Dover get wildfire smoke?
Not from local fires — Delaware doesn't have a wildfire season like the West does. But smoke from distant fires can still reach Dover when conditions line up, as it did in 2023 when Canadian wildfire smoke drifted as far south as the mid-Atlantic and pushed Kent County's particle-pollution grade down for the year.
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 2 curated PurpleAir sensors Canairy tracks in and around Dover, 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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Air quality near Dover
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