Forecast Discussion

Again today, localized Code Red and Code Orange fine particulate concentrations are likely occurring across southwestern NC as a result of active wildfires. Otherwise, daily average fine particulate concentrations in the Code Yellow range are prevalent statewide.

On Friday, the arrival of a backdoor cold front from north to south will help to lower PM2.5 levels statewide. Some precipitation is possible along this boundary, albeit light and scattered. The colder, drier, northeast flow following the fropa will settle across NC by the late afternoon/evening. Any potential rain will not likely have a substantial effect on the fires burning in the region, and some pooling of smoke/particle pollution may occur ahead of the front in the southwestern corner of the state. For these reasons, we are issuing a Code Red Air Quality Action Day for PM2.5 effective tonight at midnight (12AM 11/10/2023) through midnight tomorrow (12AM 11/11/2023) for Cherokee and Clay Counties as the Collett Ridge Fire continues to impact the area. We are issuing a Code Orange Air Quality Action Day for PM2.5 for the same time frame above for Macon County. The NC Forest Service has issued a Burn Ban for several counties until further notice; more information can be found here.

The clean air mass arriving after the aforementioned cold front should bring dry Code Green conditions statewide on Saturday, with the possible exception of Cherokee and Clay counties; Collett Ridge Fire activity will be closely monitored and the forecast adjusted here if necessary. The chance for rain in the southern half of the state returns on Sunday with another shortwave disturbance and isentropic lifting of the southwesterly mid-level flow; the timing and extent of this should come into better view in the coming days. Expect Code Green fine particulate levels throughout most of the state and Code Yellow potential for Cherokee and Clay Counties on Sunday.