Unless the trye had got a puncture and let go due to lack of air, i would suggest, the tyre has been coming apart for a little while now.
Now, having said that, i haven't checked mine either for any obvious out of roundness in the tread. Normally, when this occurs, you would pick up the problem early by running your hands over the tyre wouldn't be a waste of time
It shows use though, that a jack up and spin the wheel for a good visual is even more important.