So you want to change the weather in Skyrim. Because the godlike powers of modding have gone to your head and just because you can. But which mod should you use to change it?
Hawx Gaming breaks it down for you in this nice comparison of two popular weather-changing mods, Climates of Tamriel and Pure Weather.
Hawx puts the more established Climates of Tamriel on top overall, but he does call Pure Weather a "nice change" with its own advantages.
If you don't want to take his word for it, you can get Pure Weather
here. And Climates of Tamriel
here.