I always wondered what started that cycle lol.
If you look at 1944.....it really stands out with the number of 100 degree days compared to the rest of that decade....likewise with 1966 and 2010 of course.
1999 had most of them confined to July (similar to 1955).
1988 was more of an inland heat summer.
1977 had that one historic hot stretch and the big blackout
Scorchers outside of this pattern include 1948, 1953, 1980, 1983, 1991,1993, 2002......
1983 must get special mention because its combo of heat and humidity is unparalleled (as well as late season heat).
1991 and 1993 set the 90+ degree record at NYC and 1993 especially I remember as being wall to wall heat! and that three day super heat wave of course which I experienced again in 2010. I'm also going to include 2011-13, they were all super hot and reached 100 degrees and July 2011 had the hottest day I've ever experienced bar none. And then the big deluge came in August lol.
Cant forget 1995 either with the astonishing 130 heat index in July and then the wild fires in August.