The NFL conflicts. Or the Johnson/Jill snub. Now it's "natural disasters"? There are always storms, flood, hurricanes... and he picks the peak of hurricane season to say any such wind and he can't debate, huh?

Source: Politico
Republican presidential nominee Donald Trump said Monday that he has an “obligation” to go head-to-head with his rival Hillary Clinton in all three upcoming general election debates.
“I think you have an obligation to do the debates. I did them with the other, you know, the other cases. We had, I guess 11 debates,” Trump said about the Republican primary debates that helped elevate his bid for the nomination against 16 Republican opponents.
“Obviously I did well in the debates. Obviously according to the polls. The online polls they did right after the debates. And I think I’m doing the same thing,” he said, speaking on MSNBC.
When asked about his pre-debate preparation, Trump remained vague.
Read more:
http://www.politico.com/story/2016/09/trump-will-debate-clinton-2016-227739