I don't know what your budget is for this, but here's a nice Lilly that is a little dressier then a sundress:
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Facile remedium est ubertati; sterilia nullo labore vincuntur. I think pearls are lovely, especially when you need something to clutch. ~ AzTheta
The Real World Can't Hear You ~ GC Troll
Nice suggestions! Definitely select something sleeveless. Since you're married you won't be trying to catch the bouquet, so you could even go strapless. (The guest who caught my bouquet had a strapless dress that became topless. )
My wedding was on August 5 in Louisiana, but we had the good sense to have it in air conditioning. The guys sweltered in their tuxes anyway.