NOAA/EPA Day 3: State and local Message

Where Do Air Quality Forecasts Come From?

You're probably checking the weather forecast as you make your daily plans this summer to find out if it will be sunny or rainy – and just how hot it's going to be. There's another forecast you should check, too. Your local air quality forecast can help you protect your health when air quality in your area is poor. These forecasts, based on EPA's easy-to-understand Air Quality Index (AQI), can help people like you across the country make informed decisions about your daily activities.

Each day, state and local forecasters use a variety of tools to prepare the official AQI forecast for more than 320 metropolitan areas across the country. NOAA recently expanded its numerical forecast guidance to include the South and much of the Plains. The forecast guidance predicts maximum AQI levels for ozone for the current day and the next day. Forecasters at NOAA's Hydrometeorological Prediction Center (HPC) provide daily written discussions highlighting weather conditions for areas with the potential for high ozone buildup from June through August.

The HPC collaborates with the EPA, state and local air quality forecasters, and local National Weather Service offices through the real-time Web site http://www.hpc.ncep.noaa.gov/aqtest. When necessary, HPC will brief state air quality forecasters, as well as EPA, regarding expected atmospheric conditions affecting air quality.

State and local air quality forecasters submit their forecasts to EPA, which distributes them to the media, commercial weather service providers, the AIRNow web site and other organizations to get this information to the public. AQI forecasts are available in many local newspapers and on local television weathercasts. You also can find the forecasts, along with real-time air quality information, on the AIRNow site, at www.airnow.gov.