Labor question?

I’m already a mom of one. When I went into labor with my son, I was 40 weeks 4 days and I had cramps all day that got worse throughout the day until I was in active labor.

I am now pregnant with my second, I’m 39 weeks 2 days and I was expecting this one to come sooner but I think he will be late too. My question is, can active labor come on set out of nowhere? Or does it almost always happen where you have cramping first and then full blown labor? I know every pregnancy is different I just want to know if full on contractions can come out of the blue?