Forecast Discussion

Current hourly ozone readings are in Code Green range statewide except for Mecklenburg County where Code Yellow is being observed. Current daily averages for fine particulates are in Code Yellow range across much of the Piedmont, and Code Green range elsewhere with the exception of parts of Jones, Craven, and Onslow counties where smoke from wildfires is likely leading to localized elevated PM2.5 readings.

We'll see a similar weather pattern yet again on Thursday across the state as the center of high pressure remains offshore. South/southwest winds will increase a bit more as an upper-level trough begins to approach from the west and we see increased afternoon mixing. With no major changes to the airshed, fine particulates will likely average out in Code Yellow range again across much of the state. As for ozone, we should see enough sunshine for some ozone production and Code Yellow ozone maximum 8-hour averages are forecast for the Charlotte, Fayetteville, and Raleigh areas., although persistent winds and mixing should put a cap on ozone. Meanwhile, some ozone may also transport in from the south and mix down in the southwestern part of the state, leading to Code Yellow averages in that area. Regarding the Black Swamp Fire in Jones County, containment has increased today (Wednesday) and the acreage has remained the same. The smoke plume has shrunk in size on satellite imagery this afternoon and is a bit hard to see at times. Modeled smoke plume data is also not very impressive through Thursday. Based on this, we have decided to not continue Code Orange for Craven and Jones county for Thursday, but are still forecasting Upper Code Yellow (Moderate) to account for some smoke, so those that are sensitive should still use caution. We also are forecasting Upper Code Yellow for Onslow County due to a wildfire burning near Hubert. We'll continue to monitor both of these fires and adjust the forecast as necessary.

We'll see the pattern start to slowly break down heading through Friday and Saturday as a trough moves in. This will lead to increasing clouds and rain chances, especially over the weekend. Fine particulates will likely remain in Code Yellow range for the interior, but will slowly decrease. The increasing clouds and precipitation chances should lower ozone averages to Code Green range statewide by Saturday.