Ninth Square, New Haven Air Quality Forecast - Today, Tomorrow
Air Quality Today
Today (6 October): Air quality in Ninth Square is moderate. AQI and PM10 are moderate; PM2.5 and NO2 are fair; O3, SO2, CO, HCHO, and PM1 are good. Pollution peaks around 8:00 AM (PM10: 43.2/100).
Air Quality Tomorrow
Tomorrow (7 October 2026): Air quality in Ninth Square is good. AQI improves to good; PM2.5 decreases to good; PM10 decreases to good; NO2 decreases to good; all other pollutants stay as today. Pollution peaks around 12:00 PM (O3: 16.5/100).
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Air Quality
Today - 6 October
| Pollen species | Level | Value |
|---|---|---|
| AQI | Moderate | 43.2/100 |
| PM2.5 (fine particles) | Fair | 23.4/100 |
| PM10 (coarse particles) | Moderate | 43.2/100 |
| NO2 (nitrogen dioxide) | Fair | 26.2/100 |
| O3 (ozone) | Good | 13.6/100 |
| SO2 (sulfur dioxide) | Good | 0.4/100 |
| CO (carbon monoxide) | Good | 0.5/100 |
| HCHO (formaldehyde) | Good | 3.0/100 |
| PM1 (ultrafine particles) | Good | 14.6/100 |
Tomorrow - 7 October
| Pollen species | Level | Value |
|---|---|---|
| AQI | Good | 16.5/100 |
| PM2.5 (fine particles) | Good | 10.8/100 |
| PM10 (coarse particles) | Good | 13.1/100 |
| NO2 (nitrogen dioxide) | Good | 16.4/100 |
| O3 (ozone) | Good | 16.5/100 |
| SO2 (sulfur dioxide) | Good | 0.5/100 |
| CO (carbon monoxide) | Good | 0.4/100 |
| HCHO (formaldehyde) | Good | 3.1/100 |
| PM1 (ultrafine particles) | Good | 10.7/100 |
Local Environmental Conditions
With buildings covering much of the area around this part of New Haven, traffic and other urban emissions are the biggest local influence on air quality. Breezes off the Long Island Sound usually help ventilate the area. Home heating, especially wood stoves and fireplaces, adds smoke and fine particles in the colder months. Pockets of trees and green space help filter a small share of the particles from traffic.
Particle levels tend to be highest from November to March, when home heating and traffic add more emissions and cold, calm spells at around -2°C can leave a light winter haze over the city. From June to August, strong sunshine and temperatures around 24°C drive ozone formation, with levels peaking in the afternoon.
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Frequently Asked Questions About Air Quality in Connecticut
Is air quality bad in Ninth Square right now?
On 6 October 2026, overall air quality in Ninth Square is moderate. AQI is the main air quality indicator at 43.2/100. Pollution peaks around 8:00 AM (PM10: 43.2/100).
Will air quality be worse tomorrow in Ninth Square?
On 7 October 2026, air quality conditions in Ninth Square will be better than today, with AQI forecast at good at 16.5/100. Pollution peaks around 12:00 PM (O3: 16.5/100).
When is air pollution at its worst in Ninth Square?
Particle levels tend to be highest from November to March, when home heating and traffic add more emissions and cold, calm spells at around -2°C can leave a light winter haze over the city. From June to August, strong sunshine and temperatures around 24°C drive ozone formation, with levels peaking in the afternoon.
Are air quality levels in Ninth Square based on measurements or forecasts?
It is forecasts derived by downscaling forecasts provided by EU’s Copernicus Atmosphere Monitoring Service (CAMS) by taking into account local conditions such as traffic patterns. CAMS bases its forecast on satellite measurements of particles and chemical compounds in the atmosphere. Airmine’s services were developed with support from the European Space Agency (ESA)’s Business Applications and Space Solutions (BASS) team.
Why doesn’t the forecast always reflect wildfire impacts?
Airmine’s forecast uses CAMS (Copernicus Atmosphere Monitoring Service) as its background atmospheric model. While CAMS includes wildfire emissions, these are derived from satellite observations and are not available in real time. During rapidly evolving wildfire events, there may therefore be a delay before increased emissions are incorporated into the model. As a result, the forecast may temporarily underestimate PM₂.₅ and other pollutants associated with wildfire smoke.
During rapidly evolving wildfire events, CAMS may lag by approximately 1–2 days before increased wildfire emissions are fully represented, which can lead to temporary underestimation of PM₂.₅ concentrations in Airmine’s forecast.
Understanding the Scale
The 0–100 air quality scores represent risk levels, not direct air pollutant concentrations. Higher scores indicate higher risk.
Air Quality
| Good | 0-20 | Low air quality risk. Air quality is expected to be good, with low levels of pollution. |
| Fair | 20-40 | Generally low air quality risk. Air quality is expected to be acceptable, with some pollution present. |
| Moderate | 40-60 | Moderate air quality risk. Air pollution is elevated and air quality may be less favorable. |
| Poor | 60-80 | High air quality risk. Air pollution is high and air quality is expected to be poor. |
| Very Poor | 80-100 | Very high air quality risk. Air pollution is very high and air quality is expected to be very poor. |