Unlucky Nagasaki got nuked because the primary target, Kokura (now part of the city of Kitakyushu) was obscured by cloud cover that morning.
Yes. I had read about that somewhere once before. What I did learn new today after doing a bit of research, is that another bomb was almost ready to ship out to Tinian and several more were in the pipeline. Years ago, I had read that Little Boy and Fat Man were the only bombs in existence. From the memo at the last link I posted, it seems there was debate as to whether the bombs should be used strategically or tactically in tandem with Operation Downfall.