July 18 will be an Air Quality Action Day for lower Delaware.
There will be continued hot and humid weather with light winds shifting to the southwest by afternoon. Sunny skies will allow ozone to accumulate with Code Orange ozone expected by late afternoon. High humidity will cause a further increase in particle concentrations with the daily average in the upper moderate range.
Extended Forecast: Strong southwesterly winds on Friday will limit the accumulation of pollutants. While there is a chance of isolated Code Orange ozone, moderate air quality is expected July 19. Rain is likely ahead of a cold front on Saturday afternoon with pollutant levels dropping to the lower moderate range.