After a brief spell of cooler than usual temperatures, mainly across the South, we will warm up once again for many here in the East. It will fee like summer again for many, after all, it is still technically summer. We are in Meteorological Fall though which started September 1st. The warmth will hang around for most of this month, with the exception of a cool shot coming around the end of the month.
This is a seasonable pattern since the fall can alternate between warm and cold. After autumn arrives, the cool air will quickly rush in behind the heat and will give us our taste of fall. As of now, the cool shot does not look to be too extreme, but rather normal for this time of year.
GFS for 9/17:
GFS for 9/28: