kulrblind

Asking is a good idea, but consider these two points:

1) You have to look good -with- your girlfriend, so don't dress dumpy (sorry) if she's going to look smokin'

2) Linen shirts and pants are cool and breathable, and they look snappy and summery, and you can choose a shirt with a collar that will look great without a tie.

I'm going to a summer wedding up here in Nova Scotia, and my wife's in the party -- so I'm dealing with some similar issues. I will, however, have to dress "up" for this one.

Good luck, and take pictures!

edited because i'm a lousy editor