Forecast Discussion

Current daily average PM2.5 levels are in the Code Yellow range throughout most of the interior this afternoon. Ozone levels are holding in the Code Green range everywhere except north of the Fayetteville metro area where Code Yellow conditions are being observed.

A surface low over New England will drag a cold front across the state from the north-northwest on Saturday evening. Prior to that, rainy southwesterly flow will persist. Similar to the past several days, moderate PM2.5 concentrations are expected in much of the Piedmont and western Coastal Plain ahead of this frontal passage. Ozone may rise a bit behind the front as skies clear, but overall should remain in the Green range.

Sunny and dry conditions will return after the front clears the state on Sunday as high pressure builds in from the northwest. Both ozone and PM2.5 concentrations should drop down to the Code Green range post-frontal passage on Sunday. The center of the high will quickly move eastward and off the Carolina coast by Monday afternoon resulting in very light and variable winds across the state. Both ozone and fine particulate concentrations will gradually rise, possibly into the moderate range.