Where Does This Data Come From?
The Forsyth County Environmental Affairs Department in Winston-Salem, North Carolina, operates Triad Haze Cam. The images are taken from the top of Sauratown Mountain in Stokes County, North Carolina. Hourly ozone and meteorological data are measured at the Union Cross monitoring site, located approximately 30 miles south of the camera site in southeast Forsyth County. Hourly PM2.5 data are measured at the Hattie Avenue monitoring site in Winston-Salem, located approximately 25 miles south of the camera site.

Camera images are automatically sent via FTP from the Sauratown Mountain site. Hourly ozone, PM2.5, and meteorological data are polled by the Forsyth County Environmental Affairs Department computer system and then sent via FTP to Triad Haze Cam. A script file decodes the hourly data, calculates the appropriate averaging intervals and air quality indices, and posts the resulting information next to the latest camera images.

Always check the "Data Last Updated" marker to insure the timeliness of displayed information. Technical problems at the monitoring sites, camera system, along the internet, or at the server (or all of the above) can affect update frequency. Triad Haze Cam's status is checked frequently but not continuously during the work week. There is no weekend or holiday coverage.

Fine Particulate:
PM2.5: Suspended particulate matter with an aerodynamic diameter of 2.5 micrometers or less and is measured in micrograms per cubic meter. The PM2.5 value shown is an hourly average. There is no hourly ambient air standard. The 24-hour standard is 65 micrograms per cubic meter.

Ozone:
A reactive chemical compound of 3 oxygen atoms found at all levels of the atmosphere. Ozone is measured in parts per million. The ozone value shown is an hourly average. The hourly ambient air standard is 0.125 parts per million and the 8-hour average ambient air standard is 0.08 parts per million.

Temperature:
The ambient air temperature measured in degrees Celsius.

Pressure:
Uncorrected barometric pressure at an elevation of 285 meters (Union Cross site) in millimeters of Mercury.

Dew Point:
The temperature to which an air parcel must be cooled to achieve saturation, measured in degrees Celsius.

Wind Speed:
Wind velocity measured in miles per hour.

Wind Direction:
Wind direction is the direction from which the wind is blowing. It is measured using a compass scale of 0 to 360 degrees. North is 0 or 360 degrees, East is 90 degrees, South is 180 degrees and West is 270 degrees.

Real-Time Data Disclaimer:
All data posted on the Real-Time Image web page are raw values that are automatically collected and transferred to Triad Haze Cam. They have not been validated by human review and may contain errors. Real-time data must be interpreted with caution and are provided for public awareness only. They should not be used in any medical or scientific study. Contact Forsyth County Environmental Affairs Department to obtain quality-assured data summaries or access to fully-validated raw data.