Laura has Wendy been in the sun? In a window in the sun? The ultraviolet rays can change the pigment in the nose, so it may be that and not an illness. Check her gums and see if they are white streaked or pale? Press in on them and see if they change color and pink up right away?
I have the same problem with my kitty, his nose turns white if he has to go to the vet. I think it has something to do with him being nervous or stress out. Even in the summer, his nose turn white. I guess because it is really hot out. Maybe that is probably why your kittie nose turns white but I would worry about it.
my kitty Pixel's nose I find is kinda darker pink to nearly brown on its outter edges and the center is normal pink. Is this a reason for concern? Her nose is still wet, not dried out or anything. Any ideas?