This mod is not working and has not worked for over a year look at the support requests. Personally I'm done buying from Codefling as they won't even refund you if the developer don't support his work, and Codefling moderates all reviews on their site. It took me 3 days back and fourth with their moderator to leave a review on another plugin that he edited to be less impactful to the seller. Codefling does not want honest reviews they just care about sales. Money is the root of all Evil!!!

Ok, so I have been using a different paid weather control plugin for a while now, so I was intrigued by the offer to look at this plugin and give an honest review and feedback, since I do like to mess with weather on my server.  First : I'm not going to name the plugin I was using. It is in it's own right a fine plugin and if you prefer it, fine by me. This is just my honest opinion.

That said, I've moved my server to this plugin permanently. A major consideration was that this plugin runs under Harmony and therefore has less deployment issues and possible problems when updating, but also how well the system works, and the amazing effects you can achieve. You can have weather that fades in and out, whole climate systems so areas of the map can have not just a static weather condition, but dynamic weather within the parameters you can set. There are SO many factors you can tweak you can pretty much make any weather condition possible, and a fair few impossible ones that look quite otherworldly.

The other consideration was feedback. The developers are responsive, are willing to listen to ideas and make tweaks to the plugin for those who want to push it's limits or use it in unusual ways, and friendly too. The few concerns I had were addressed immediately, leaving me very satisfied with the dev's response times and dedication.

This product received for free.

This is the absolute best weather mod I own. It will be permanently on my server for now on. You can adjust so many weather features with this, it isn't funny. Highly recommended. An admins new toy, and my players love the effects I can achieve on the server with it!

So I wanted to give an honest review, and I spent about a solid week checking out this mod.. I love that it works straight after restart no need to mess with it it's just works..
I love the realistic weather, it actually clouds over when it rains. I've tried many "weather"  plugins and they do work but also can cause lag on a heavily modded server (I run about 190 plugins on an event server) and this mod you can't even tell it's there.. 
The Smoothness and realistic weather of this mod alone is worth it.

I added a small clip of it starting to rain, and you can see the clouds actually covering the sun for a heavier rain with clouds getting darker, it was 10 in the morning (Rust time)
https://medal.tv/games/rust/clips/ETcmOMQA73Zao/d1337dg3dEdJ?invite=cr-MSxjbFUsMTc0NDkzMjks