What to wear if a tri-suit won't fit?

[Tri Girl]

Okay, now, for the clothes...I wear the tri-suit under the wetsuit for the swim? And then take the wetsuit off and bike in the tri-suit with my cycling sandals - Keen, on sale now at REI - and then switch to my running shoes for the run, and slip on a skirt over the tri suit?

Yes, that's right. Sounds like a good plan. You've got it all figured out. It sounds a lot like what I'd wear in a race.

so the water will only be in the low 60s, if that.

ONLY in the low 60's. If you've ever swam in 60 degree water, you'd be surprised at how cccccccooooold that is. USAT sanctioned events are wetsuit legal up to 78 degrees (you can wear a wetsuit from 79-84 degrees, but you're not eligible for awards). I wear a wetsuit unless it's not legal, as even 70 degree water is very cold to me. If the water is indeed that cold- you would probably want to wear a wetsuit as you'll freeze your little bits right off.