Yeah, we didn't even see that in 1993. I think the last time we hit 90 that year (the 39th time, which tied the record from 1991, was on Sept 15, on my bday lol, with Hurricane Emily, a Cat 3, off the NC coast.) We might have hit 90 later than that in 1991, I forget, I think it was somewhere between the 21st and 24th? 1983 was the champion of long lasting heat and humidity and the previous record holder- we had a really hot September that year, hitting 99 or 100 in September (on 9/11 I think) and 95 as late as the 21st and our last 90 that year was around the 24th or 25th. Latest 90 I can remember was in a year that wasn't even that hot, 2007, when we hit 90 at JFK on October 9th or 10th. The only time it ever hit 90 here in October. That year we hit 70 on the 11th anniversary of the Jan 1996 blizzard in early Jan, and 90 in the first half of October. But we had a cold second half of winter with inches of ice and sleet events instead of snow. Really strange year.
Typically we switch to a true fall pattern in the third week of September, right in time for the equinox.