A storm blew my tree on the neighbors roof, who is legally responsible?

A storm just snapped a perfectly healthy tree in half and onto my neighbors roof. The tree is most definitely from my yard. I live in Georgia and am wondering if I am responsible for this, or is he? Oddly enough the opposite situation happened on Mother's Day. A huge tree, I strongly suspect as his, fell and pushed several large trees onto the entire back section of my fence. My insurance paid with no questions as to whose tree it was. I still haven't finished cleaning up that mess. sigh.

I realize it is neighborly to help him, I am just wondering about whose insurance would be used and the legalities.

The legal answer is that neither you nor your insurance have any liability. If the tree was not properly cared for and it fell over in a storm as a result, you would be liable, but that's not the case here. The tree was reasonably cared for and healthy. The accident was an unforeseen event. It is considered an act of god. You are not liable for the damages and you are not even liable for the clean up and removal of the debris.
You did, however, pay with your insurance and you are cleaning it up. This makes you a good neighbor. You will be awarded with good karma points for that.

No one is responsible unless there was negligence involved, like there was something wrong with the tree that you did nothing about, or if you we trying to cut the tree down by yourself without the necessary equipment.

I does make for an awkward situation though.

it was the winds fault. the tree is partly at fault cuz it wasn't strong enough to stay in the ground but if theres anyone to blame it the wind. i curse the wind!

the neighbors insurance because it is now on his property

Ahh... isn't it mothers natures fault? Why would someone be held responsible to something they have no control of?