Good luck man..
Just to prepare you for some negativity as well though, since everyone else is being positive..(which is great. Always be positive)
My mother isn't supportive at all. My parents divorced right before I came out and my dad was supportive from the beginning(though not as much as he is now. He is now INCREDIBLY supportive.) and my mom gave me the whole "I love you no matter what" speech, but has since regressed and said that I need to "get off this Testosterone ->-bleeped-<-"(yeah, as soon as I began HRT, it became VERY real to her that changes were happening) and came at me with comments like "just strap on a dick and pretend to be a boy without taking ->-bleeped-<- that will kill you". She deleted me as a child on Facebook because she couldn't stand the embarrassment of having me listed as her "son" (though I didn't change anything on FB until I was 7 months on Testosterone and it was already obvious to everyone). I have given her time; it's been over a year. I also took things as slowly as possible and I am still VERY UNDERSTANDING of my dad slipping up and calling me my birth name and "she". It doesn't happen often, but as I said it's only been a year and he's been calling me that name for 21 years. It's difficult to adjust. I view my transition as not only a transition for me, but for everyone that I love as well. So when things like this happen to you, just realize that if they say they're supportive and they're showing signs of improvement then you can't be mad at them.. If my mom was trying, this would be a whole different can of worms.
She barely talks to me, and that's fine. I'll always love my mother, but I can't have negative influences in my life. I've steered clear from her until she can accept the fact that I am NOT going to stop taking Testosterone, I am NOT going to stop transitioning, I WILL get my name legally changed, and I WILL move out of state(sorry about that last thing, she actually is against me moving out of state after completing my bachelor's, and I'm just venting LOL)
However, if your parents are still together and they're close to each other... and they formulate the same opinions on things, it should probably work out better for you. My dad is educated and my mother is not; so explaining things to her - no matter how far I go back, no matter how easy I make the terms - does not work. My dad was not educated on THIS subject, but he has enough intellect to formulate ideas and to grasp what I am saying. My mom either A) doesn't give a ->-bleeped-<- B) doesn't listen or C) doesn't understand, as she says she doesn't. I try to go back and go more slowly when explaining things, but she cuts me off and says she doesn't care. So I believe it's a mix of AB and C.
It all goes down to being how your mom is, how well she understands things, or is willing to try and understand things. If your dad is that type of person, and they're still together then I definitely think the odds are in your favor. Just be prepared.
Good luck
