With the help of regional pollution monitors and weather forecasts, environmental agencies are able to predict local air quality much like they predict the weather. This year marks the beginning of daily air quality forecasting and reporting for ground-level ozone in the Northern Shenandoah Valley. Daily forecasts for Winchester and Frederick County will be issued each afternoon by 3:30 p.m. during the summer ozone season (May 1 - September 30) in coordination with the Virginia Department of Environmental Quality and Maryland Department of the Environment. They may be found here along with current, real-time air quality data for ground-level ozone. Additionally, if you would like to receive daily air quality forecasts by e-mail, please contact us.

The U.S. Environmental Protection Agency (EPA) has created a tool to make information about air quality as easy to understand as your local weather forecast. The Air Quality Index (AQI) provides simple information about local air quality, along with health concerns and advisories for varying levels of ground-level ozone pollution. The AQI is divided into five categories, ranging from Good to Very Unhealthy, with each category and its AQI value corresponding to a different level of concern for public health. Higher AQI values indicate increased levels of ground-level ozone pollution and greater concern for public health. In addition, a specific color is assigned to each AQI category, making it simple to quickly assess local air quality. Daily ground-level ozone forecasts for Winchester and Frederick County will correspond to AQI categories and color codes.

Air Quality Index
AQI Color	Levels of Concern	Action Guide
Green	Good	None
Yellow	Moderate	Unusually sensitive people should consider reducing prolonged or heavy exertion outdoors
Orange	Unhealthy for Sensitive Groups	Active children and adults, and people with lung disease, such as asthma, should reduce prolonged or heavy exertion outdoors
Red	Unhealthy	Active children and adults, and people with lung disease, such as asthma, should avoid prolonged or heavy exertion outdoors.  Everyone else should reduce heavy or prolonged exertion outdoors.
Purple	Very Unhealthy	Active children and adults, and people with lung disease, such as asthma, should avoid all outdoor exertion.  Everyone else should avoid heavy or prolonged exertion outdoors.
Maroon	Hazardous	Everyone should avoid all physical activity outdoors.

Note: A measurement of 75 ppb is considered unhealthy or a Code Orange alert. Please review the chart above.

Visit the links below for local air quality data and information.

Virginia Department of Environmental Quality:

Ozone Forecasts and Current Conditions

Hourly ozone data for Winchester-Frederick County

Join DEQcast--a new subscription-only service to receive DEQ air quality forecasts and/or health alerts via email.  Sign up today at http://www.deq.virginia.gov/lists/. 

DEQ Air Quality Hotline: (804) 698-4444

Environmental Protection Agency:

EPA AIRNow Data for Winchester, VA: Current conditions map, 2-day ozone forecast, monthly archives of ozone data.

Animated Ozone Map: Follow the links for local air quality to view an AQI map for Virginia/North Carolina as well as an animated map of yesterday's ozone movement.

Air Quality Index in Google Earth: Use this new AQI tool to quickly see air quality across the country, then click on a specific location to see that city's AQI forecast and current levels of ozone or particle pollution.

Other Winchester-Frederick County Ozone links:

The Weather Channel: Air Quality State Reports

Weather Underground: Conditions and Forecast for Winchester, VA

Weather Underground: Northeast Regional Air Quality map

To receive daily ozone forecasts for your area, please contact us!

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