Possible an Eastern Gray Tree Frog, Hyla versicolor, or a Cope's Gray Tree Frog, Hyla chrysoscelis, (I'm not positive if the Cope's are in your area, the two versions are visually indistinguishable). Their colour can vary greatly, near white is possible. They are bumpy and I've seen them referred to as "Tree Toads". They have sticky toe pads for climbing stuff.

I have pics in my albums and there is a link to a care article on the left for more info about them (google as well of course) so you can see if my guess is any good