Description:
If you sleep while it's raining, the rain won't stop after you wake up, and it will rain infinitely. Also, undead mobs take damage from rain.
Fix: Quitting and joining back your world fixes it.
Attachment: The file size is too large, so I uploaded it on YouTube:
You can see on the video what I mean.
One thing to note is that it was raining nonstop for half an hour. In the video, you can only see the last 2 minutes.
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Comments

Thank you for your report!
We're tracking this issue in MCPE-131325, so this ticket is being resolved and linked as a duplicate.
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