Jesus said it would be like the days of Noah. Men would be eating and drinking, marrying and being given in marriage, and then...it would be over. That's part of the messianic message. Do you believe everyone will be saved? And by saved I mean preserved alive. When the rains came the people likely figured something not so good was happening to them. But Noah followed God's directions and he and his family were kept alive through the flood. The Bible says every eye would see him. But how, and what would it mean? Jesus foretold that. In reference to that, here is what was said
"For just as the days of Noah were, so the presence of the Son of man will be.
38 For as they were in those days before the Flood, eating and drinking, men marrying and women being given in marriage, until the day that Noah entered into the ark,
39 and they took no note until the Flood came and
swept them all away, so the presence of the Son of man will be. (Matthew 24).