Air Quality in New Haven, Connecticut — Live
Live readings from PurpleAir sensors across New Haven — with free alerts the moment the ozone climbs.
Live New Haven AQI from nearby PurpleAir sensors loads when this page opens in a browser, along with a live sensor map covering New Haven and Hamden, West Haven, East Haven, North Haven.
New Haven's air is unremarkable most of the year — this is a harbor city on Long Island Sound, not a valley or a basin, and there's no refinery or steel mill upwind driving daily pollution. The exception is summer. On hot, sunny afternoons, exhaust from the New York City area rides a southwest wind out over Long Island Sound, gets trapped low over the Sound's cool water, and then rides the afternoon sea breeze straight back onto the Connecticut shoreline as ground-level ozone. It's a pattern researchers have measured directly at monitoring sites in New Haven itself, and it's serious enough that in 2024 federal regulators reclassified New Haven County's ozone problem as more severe, not less.
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.
New Haven's summer ozone is mostly someone else's exhaust
The Long Island Sound Tropospheric Ozone Study (LISTOS), a NASA- and EPA-backed research campaign, ran ground stations in New Haven alongside Westport, Hammonasset State Park, and Outer Island through the summer of 2018. What it confirmed is a mechanism specific to this coastline: the Sound's cool water holds the New York City area's ozone-forming exhaust in a shallow, stable layer just offshore, and as the land heats up in the afternoon, the resulting sea breeze pushes that same plume straight onto the Connecticut shore — New Haven included.
That transported pollution is why New Haven County, along with Fairfield and Middlesex counties, is part of the New York-Northern New Jersey-Long Island ozone nonattainment area. In July 2024 the EPA agreed to a request from New York, New Jersey, and Connecticut to reclassify that whole region from Moderate to Serious for the federal ozone standard — an acknowledgment that despite the region's own cleanup efforts, the summer ozone problem here isn't going away on its own. The American Lung Association's 2025 State of the Air report gave the New Haven-Hartford-Waterbury metro area an F for ozone, ranking it 38th worst in the country.
Tweed Airport adds a newer, more local worry
In June and July 2023, Tufts University researcher Neelakshi Hudda set up twelve monitors around Tweed New Haven Airport and drove instrumented routes through the surrounding streets. She found that unregulated ultrafine particles — the kind thrown off by burning jet fuel — spiked measurably, both outdoors and inside nearby homes, whenever planes took off or landed, with the effect strongest within about half a mile of the runway and shifting with the wind.
The findings landed in the middle of a live local fight over the airport's plans for a new terminal and a longer runway, and Tweed has since offered a Residential Indoor Air Program supplying air purifiers to eligible households nearby. Separately, the city of New Haven has installed its own network of air-quality sensors around town — a sign that, airport politics aside, people here want a real, local answer to what they're breathing, not just a regional forecast.
The one summer the sky actually turned orange
New Haven doesn't have a wildfire season of its own, but it got a preview of one in June 2023, when smoke from fires burning in Quebec, Ontario, and Nova Scotia drifted south into New England. On June 7 the sky over the Connecticut shoreline turned a deep orange-brown, schools canceled outdoor activities, and air quality alerts covering New Haven and the rest of the state warned residents to stay inside with the windows shut as readings reached Unhealthy and Very Unhealthy levels. A second, milder round of Canadian smoke returned at the end of the month.
It was a genuine outlier, not a preview of a new normal — nothing like it has repeated since, and it isn't the kind of thing New Haven needs to plan a season around the way a California or Pacific Northwest city does. But it's a reminder that even a city whose air problems are normally slow and seasonal can get a fast, ugly surprise from a source thousands of miles away, which is exactly the kind of change worth a sensor check rather than a guess from the color of the sky.
New Haven air quality FAQ
What is the air quality in New Haven right now?
This page shows the current AQI for New Haven, 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 does New Haven's air get worse in summer?
Summer heat and sun cook up ground-level ozone, and New Haven sits directly downwind of the New York City area across Long Island Sound. On hot, sunny afternoons a sea breeze carries that transported exhaust back onto the Connecticut shoreline, which is why New Haven County's ozone problem was reclassified from Moderate to Serious by the EPA in 2024.
Does Tweed Airport affect New Haven's air quality?
A 2023 Tufts University study found that ultrafine particles from jet exhaust spike noticeably near Tweed New Haven Airport during takeoffs and landings, especially within about half a mile of the runway. It's a smaller, more localized issue than the region's summer ozone, but it's a real one, and it's part of why the airport now offers an indoor air purifier program to some nearby households.
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 New Haven data come from?
Readings come from PurpleAir's network of laser particle sensors across New Haven 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.