I have an AFK Fish Farm and since you get more things when it rains I usually just entered / weather rain 100000. Unfortunately I had to find out that it still thundered. As a result, after a few hours of AFK Fish Farms one night, some of my buildings burned down because lightning hit the wood on the houses.
So is there a way to really ONLY let it rain? Clear weather is not a problem, it always stays clear. But when it rains, thunderstorms sometimes occur. Stupid that there's then rain and thunder as a command.
You can only make it rain by using the / gamerule command:
/ weather rain
/ gamerule doWeatherCycle false
If that doesn't work with Philluminat's answer, you can try plugins (if you can xD)
But why shouldn't it work xD
When I wrote my answer, the questioner didn't give Philluminat "Helpful", so I thought his answer didn't work xD
