Ummm...
The only way to tell what she is het for is by breeding her to different morphs. If you wanted to know if she was het for amel, then you would breed her to an amel. If she is het for amel, then you would get approximately 1/2 amel and 1/2 normals het amel from the breeding. If you breed her to your snow and she is het snow, then you would get approximately 25 % each of the following: snow, anery het amel, amel het anery, and normals het snow. If she is only het amel when you breed her to your snow, then you would get approx. 50% amels het anery and 50% normals het snow.
I hope this helps! By the way, snow will always produce more snows. I guess it is possible for them to produce something else if they are both het for an identical additional gene. For example, if they were both het caramel, then they would have approx. 50% snow het caramel, 25% butter anery, and 25% Snow. I don't know if caramel is a trait they can even be het for, however. I just chose the first one that popped into my head...remember this is just an example.