According to anobituaryposted this week by his family, Hume died July 13.
A cause was not stated.
The film because a cultural touchstone, drawing more than 100 million U.S. viewers.

Edward HumeCourtesy
The film stunned audiences with graphic and, for the time, realistic special effects depicting multiple nuclear strikes.
A grim ending introduced many viewers to the concept of nuclear winter.

‘The Day After’ABC/Courtesy: Everett Collection