Because there are some people who will take advantage of anything, please consider carefully any appeal for aid that isn’t from a well established charity.
I’m recommending the American Red Cross, because they are well established and they specialize in disaster relief.
You will probably want to specify a donation for Hurricane relief, but don’t forget the Red Cross also facilitates communication between members of our military and their families. There will certainly be a lot of soldiers wondering about their loved ones in the devastated areas.
If you you prefer an alternative to the Red Cross, please consider Mercy Corps.