I said during one of my weather posts that I think notable weather events (and other unusual events) probably make a bigger impression on young people than they do on older folks, which may partially account for the fact that I still remember the summer of 1954, even though it was almost 60 years ago. However, I recognize that we have had some very hot summers in more recent times as well.
One that I recall somewhat vividly is the summer of 1980. The heat wave was not quite as extreme as in 1954. For instance, the high temperature in Springfield, Missouri, in 1980 occurred on July 30 with a reading of 105 degrees. By comparison, the summer of 1954 had several days when the temperature soared above 110. However, 1980 was probably worse in terms of how long the unusual heat lasted. The heat wave started about June 22 and did not abate until September 17. The fact that the heat wave extended well into September several weeks after school had started is the part I remember most vividly about the summer of 1980. I was teaching school at the time, and the school did not have air conditioning. The mornings weren't bad, but afternoon classes were torturous for both teachers and students as temperatures approached or passed 100 degrees day after day.
The drought and heat wave of 1980 may also have been a little more widespread than the one in 1954, as it covered not just the Ozarks and not just the Midwest but even parts of the East. It may have been more deadly than the 1954 heat wave, too. Approximately 1,250 people died nationwide as a result of the 1980 heat wave (153 in St. Louis alone). I wasn't able to find an estimate for 1954.