connecting to airport disk from windows

I've managed to connect to my airdisk (on my home network) from my office using my mac. It's a great way to have access to all my music while working. Problem is, I can't figure out how to do the same from a windows machine. I know the ip at home, and i just use apple-k to access it from my mac, but nothing that I enter into "add new network place" seems to work. I know the airdisk is seen as an afp share, but I think there should be some way to access the airdisk from a windows machine over the internet...

It is formatted as osx extended, but I feel like that should not be an issue. I access and use the drive perfectly fine from a windows machine when I am on the local network. I don't see why it being on the internet would affect that aspect.