Maybe at sign up it could be suggested that members enter their zone or at least State In Signature 

I second the motion!

Yes a lot of us have mentioned that in past, but come to think about it thats not seen when a member signs up unless he reads old posts and then goes to control panel to fix it.
What you gentlman are suggesting is a great idea !
At sign up if its not already there cause i dont recall a suggestion of that, good idea guys!