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.

Live Dover AQI from nearby PurpleAir sensors loads when this page opens in a browser, along with a live sensor map covering Dover and Camden, Wyoming, Smyrna, Cheswold.

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.

Canairy watches the sensors around your home, your kids' school, and everywhere else you care about, and tells you in plain English when the air changes enough to matter.

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?

This page shows the current AQI for Dover, calculated from PurpleAir sensors across the city and updated continuously. The map below shows every live sensor, so you can check the reading closest to your own neighborhood.

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 AQI level is unhealthy?

Under the US EPA scale, AQI 0-50 is Good and 51-100 is Moderate. From 101 the air is Unhealthy for Sensitive Groups - kids, older adults, and people with asthma or heart conditions - and above 150 it's Unhealthy for everyone. Canairy translates these numbers into a plain-English verdict, like whether to close the windows or move a workout indoors.

Where does Canairy's Dover data come from?

Readings come from PurpleAir's network of laser particle sensors across Dover and surrounding towns, cross-referenced with government monitors and the Google Air Quality API. You can see every sensor behind your numbers on the live map - there's no black box.

Is Canairy free?

Yes. The Canairy app is free to download and includes live air quality for all your saved places, plain-English verdicts, and free push alerts when the air crosses your threshold. A paid plan adds extras like SMS text alerts.

Get Canairy free on Google Play.