I wanna start by saying I am not trans, so please, if my comment is offensive or insensitive, let me know and I'll delete it.
I was thinking about the temperature effect you described. While I have no other point of reference, I can tell you that with higher temperatures (may it be weather related or just cozy warm clothes) I tend to feel more femme too. This sensation lessens when I feel cold, sometimes vanishes completely. I'm assuming it's tied to the hormones, but I don't know.
In any event, I hope someone with more experience can answer your question better.