I have two sheet cakes for the same party due this upcoming weekend. I am planning on using fondant colored dark blue to cut the letters out of. The cake itself will be iced in white. As far as I know, it is an outside graduation party so the cakes will be outside, in almost 90 degree weather. Is there any chance of the blue from the fondant discoloring the white icing? I plan to make the letters in advance, like today or tomorrow and let them dry before putting them on the cake Friday night. Delivery is Saturday and they will be in my fridge all night.

The only chance would be when/if there is a sudden big change in temp.......like going from the frig to 90 temps. caUSing sweating. Unless it has a filling needing to be refrigerated, no need to put cake in frig overnight.
If you must......then can you wait to add the letters after the cake has returned to room temp in the a.m.?

Well I always fridge my cakes, but I guess they don't need to be, there is no filling in them and they are iced in buttercream dream icing from this site.

I don't plan on putting on the letters until friday night. Should I leave the cake out of the fridge all day friday so it's house temp when the letters go on, and then leave it out again overnight and up until del. time on Saturday? Our house is usually set around 75-77

would it be better to have the letters cut out in white fondant, and then just airbrush the color onto them, instead of dying the fondant?

Personally, I'd do the white fondant and air brush in blue to be safe, but I've not done it too much myself.

As long as you don't get it too wet when attaching it shouldn't bleed on to the white.

thanks everyone. I went ahead and died the fondant. I plan on taking the cakes out of the fridge friday morning, letting them set out all day in the house (77-78 degrees) and either friday night or saturday morning assemble the letters on the cake. The grad party is at 4 p.m. outside (84-88 degrees) and I'm really hoping they do ok. But I'm hoping like kakeladi said, without a huge temp change, and with the cakes already have sweated out, there shouldn't be much bleeding, if any at all. Should I have the a.c. on in the car when we deliver? Or no?

Definitely run the air in the car - no need to suffer, your cake will be fine!

ok thanks, one more question! Do you think the cakes will be ok left out all day on friday if I put them in their boxes? I could leave them out on the counters not in their boxes but if possible, I would prefer to have them covered.

I store my cakes on the counter in their boxes. Keeps them safe from light, dust, etc..

ok that's what I was thinking .. thanks!