Do it! I would say if you have a great date on Thursday, then you'll both have two weeks to think about how much fun you had, or how awesome it's going to be to continue making out, kissing, whatever the next time you see each other.
Not seeing each other for three weeks may be a little long... what if interest wanes? Especially since it's so early on -- only two dates in.
Haha, it shouldn't be as difficult as it was when we were younger. The "games" are old and tired - it's best to be up front, and don't worry about waiting this amount of time to do this, or that amount of time for him to do this, etc. I'm learning that myself.
Anyway, I say go for it - ask him out. Does he know you're going out of town? If so, I wonder why he hasn't stepped up himself to try and see you before you go...