80 NC counties and 1 VA county are under alert, including Wake, Cumberland, Durham, Johnston, and Orange counties. Details
Published: 2008-04-20 13:39:22
Updated: 2008-04-20 13:39:22
Posted April 20, 2008
By Jane Bell
MIKE MOSS SAYS: Jane, The Airnow site has archives where I could look up the observed air quality readings for the day you're referring to (Friday Apr 18, 2008) but does not have an archive of the forecast images. I assume you were seeing Code Orange forecasts for the Raleigh and Fayetteville areas, and judging from your question these must have been among the higher forecast levels in the U.S. - generally, higher code forecasts are associated with bright sunshine, warmer than normal temperatures, light winds and limited vertical mizing of the lower atmosphere, often due in part to sinking air associated with a slow moving high pressure center over the region. While I don't know the details of the Air Quality forecasts issued by the NC Division of Air Quality on Friday, I do know that general set of conditions was in place on that day across this region (the high at RDU was 86 degrees, 13 degrees above normal and skies were mainly sunny) and we may have been one of the few locations in the country where the entire combination of factors was in place to result in an Orange forecast.