Does the concert go on in the rain or get postponed?

It depends on artist, I just saw Bob Seger and it poured almost the whole show, poncho really helped

Definitely depends on performer, venue is good for setting up a website with hourly updates, example is Adam Sandler,

Rain or shine bring ponchos

Yes the show will go on in the rain, so be prepared to get wet (bring a poncho and shoes you don't mind getting soaked if you can). It will only be postponed if there is lightning. If the storm passes quickly the show will resume, but if it's slow moving or the lightning is touching down around the venue the show will be cancelled.

Depends on the performer I suppose. Typically its rain or shine