On Friday, October 10, 2014 10:53:17 AM UTC-5, Casper wrote:
I am getting ready to replace the wood doors on my shed. I am going
with the same materials, except I am chainging the hinges.

Originally I was going to replace the enitre doorway with a double
steel door/frame....
Instead I opted to replace with same wood

I'm supposing you are making/building your new (double?) doors & frame.

Any good quality hinge is recommended. You would need to gauge, for yourself, the weight of the doors, as to how many hinges would be best. Maybe, put two on, then if you find a third is necessary, add an additional, later.

As for as water entering the shed, build your framing as you would a home's entrance: Good sound door stops, a good heavy duty sloped threshold, maybe some weather stripping, appropriately flash/seal the installation of the frame to the rough wall, etc. Caulk well under the threshold. Since, I suppose, you are removing the old framing/threshold (maybe exposing the floor framing, under neath), make sure the floor joists/supports are up to par, solid, etc.... i.e., do a good inspection of the supports and flooring, while you're at it. Has any of that gotten wet, in the past, and may be needing some maintenance or additional support?

Sonny