EPA AirNow data · preliminary
Air quality right now in U.S. areas
OpenAir shows the current Air Quality Index (AQI), today's and tomorrow's forecasts and hourly monitor readings for 873 U.S. reporting areas, using public data files from the EPA AirNow program. Of 726 areas with a current reading, 3 are at Unhealthy for Sensitive Groups or worse. The latest reading in this snapshot is from Oct 28, 2026, 2:00 AM EDT; the AirNow file was published Oct 28, 2026, 2:12 AM EDT.
Find your area
Search AirNow reporting area names and about 300 of the largest U.S. cities (a city links to its nearest reporting area).
Worst air quality right now
The 10 reporting areas with the highest current AQI, any pollutant. Each value is the latest hourly reading the local agency sent to AirNow.
| Area | AQI now | Main pollutant | As of (local) |
|---|---|---|---|
| Indianapolis, IN | 155Unhealthy | PM2.5 | 2:00 AM EDT |
| Lake Elsinore, CA | 141Unhealthy for Sensitive Groups | PM2.5 | 11:00 PM PDT |
| Little Rock-North Little Rock, AR | 113Unhealthy for Sensitive Groups | PM2.5 | 1:00 AM CDT |
| Aurora and Elgin, IL | 92Moderate | PM2.5 | 1:00 AM CDT |
| Terre Haute, IN | 90Moderate | PM2.5 | 2:00 AM EDT |
| North and West Suburbs (Chicago), IL | 86Moderate | PM2.5 | 1:00 AM CDT |
| Susquehanna Valley, PA | 85Moderate | PM2.5 | 2:00 AM EDT |
| Lake County, IL | 83Moderate | PM2.5 | 1:00 AM CDT |
| Pittsburgh, PA | 83Moderate | PM2.5 | 2:00 AM EDT |
| Kettle Moraine South, WI | 80Moderate | PM2.5 | 1:00 AM CDT |
How the AQI works
The AQI turns pollutant levels into one number from 0 to 500. Higher means more pollution and more health concern. An AQI of 100 lines up with the national air quality standard, so values above 100 are the ones to watch. Each area reports the AQI of whichever pollutant is worst, usually ozone or fine particles (PM2.5).
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Forecast to be unhealthy
Areas where the local forecast for today or tomorrow is Unhealthy for Sensitive Groups (AQI 101+) or worse. Forecasts are issued by state and local air agencies, usually once a day.
No reporting area has a forecast of Unhealthy for Sensitive Groups or worse for today or tomorrow in this snapshot.
AQI categories
Good
AQI 0–50 · 544 areas now
Air pollution is low and is not expected to affect health.
Moderate
AQI 51–100 · 179 areas now
Air quality is acceptable for most people. A small number of people who are unusually sensitive to this pollutant may notice effects.
Unhealthy for Sensitive Groups
AQI 101–150 · 2 areas now
People in sensitive groups may have health effects. Most other people are unlikely to be affected.
Unhealthy
AQI 151–200 · 1 areas now
Anyone may begin to feel health effects. People in sensitive groups may have more serious effects.
Very Unhealthy
AQI 201–300
A health alert level: the risk of health effects is higher for everyone.
Hazardous
AQI 301–500
An emergency-level condition: everyone is more likely to be affected.
Browse by state
- Alabama 8
- Alaska 5
- Arizona 15
- Arkansas 3
- California 162
- Colorado 16
- Connecticut 13
- Delaware 4
- District of Columbia 1
- Florida 44
- Georgia 11
- Hawaii 11
- Idaho 25
- Illinois 14
- Indiana 13
- Iowa 7
- Kansas 5
- Kentucky 11
- Louisiana 8
- Maine 8
- Maryland 10
- Massachusetts 11
- Michigan 14
- Minnesota 17
- Mississippi 6
- Missouri 11
- Montana 17
- Nebraska 8
- Nevada 11
- New Hampshire 11
- New Jersey 10
- New Mexico 11
- New York 8
- North Carolina 94
- North Dakota 4
- Ohio 8
- Oklahoma 10
- Oregon 44
- Pennsylvania 13
- Rhode Island 3
- South Carolina 8
- South Dakota 8
- Tennessee 13
- Texas 17
- Utah 16
- Vermont 4
- Virginia 12
- Washington 48
- West Virginia 9
- Wisconsin 15
- Wyoming 18
Frequently asked questions
- Where does OpenAir get its air quality data?
- From public data files published by the U.S. Environmental Protection Agency's AirNow program. AirNow collects readings and forecasts from federal, state, local and tribal air quality agencies. OpenAir is not affiliated with or endorsed by EPA, AirNow or any of those agencies.
- How current is the AQI shown here?
- OpenAir checks AirNow about once an hour. Every page shows the time of the reading it is based on. If an area page has data more than about an hour old when you open it, your browser downloads the newest AirNow file and updates the numbers.
- Are these official air quality measurements?
- No. AirNow data are preliminary: they are not fully verified and may change. They are meant for reporting and forecasting the AQI, not for regulatory or official decisions. Verified data are kept in EPA's Air Quality System (AQS).
- What is a reporting area?
- A city, metro area or region for which an air agency reports the AQI and, in many places, issues a daily forecast. AirNow currently lists 873 U.S. reporting areas. Some areas share monitors, and some have forecasts but no current reading.
- What AQI is unhealthy?
- An AQI of 101 to 150 is Unhealthy for Sensitive Groups. At 151 and above, the air is Unhealthy for everyone, and it gets worse at 201 (Very Unhealthy) and 301 (Hazardous). An AQI of 100 matches the national air quality standard for that pollutant.
- Why can my AQI differ from another app?
- Apps may use different monitors, low-cost sensors, averaging periods or update times. OpenAir shows the AirNow reporting-area value as received, plus hourly NowCast values from regulatory-grade monitors.
Preliminary data. AirNow readings and forecasts come from federal, state, local and tribal air quality agencies. They are not fully verified, may change, and must not be used for regulatory or official decisions; official data are in EPA's Air Quality System. For the latest official readings and advisories, check AirNow.gov and your state or local air agency.
This page is general information, not medical advice. If you have symptoms or a health condition, follow your doctor's guidance.
Wildfire smoke in your area? See what to do when smoke is in the air and the official AirNow Fire and Smoke Map.
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