The Rain Collector block didn't work, although I used Weathers, Storms, and Tornadoes mod so I think you should add support for that mod.

Agreed, I noticed it doesn't work with Weather2. Kind of odd it doesn't have mod compat...

Weather2's API suggests that it's a laggy operation to check blocks for their weather, so it could be very tricky to implement without becoming a lag source
If I can figure out a way to safely implement it, I will

perhaps you could make it just detect the current weather, and fill up if it's raining/thunder/etc?

Weather2's API suggests that it's a laggy operation to check blocks for their weather, so it could be very tricky to implement without becoming a lag source
If I can figure out a way to safely implement it, I will

thank you ^-^