we are currently training as well, and it is frustrating, but i let spike outside when he needs to go. i live in the north and he loves the snow!! i dont ever leave him out for very long and he does have a jacket to wear as well. (im assuming you mean 30 degrees farenheit)
I have a long bell hanging on my door for my shepherd who rings it when he wants to go out, spike picked right up on that too! he knows if he rings the bell he gets to go out, if he goes out, he gets a treat, the last bit of the equation is that he needs to POTTY when hes out LOL (he does sometimes, but sometimes not, we're working on it!)
Patience...patience...patience...
