In the new snapshot, using spectator mode to go inside of unloaded chunks, it rains in the nether. I think this is caused because of the particles in the biomes. The unloaded particles might default to rain before it loads properly. This happens too if you TP long distances in creative mode.
MC-177856
When in unloaded chunks in the nether, it rains.
Resolved
Duplicate
1
(Unassigned)
Unconfirmed
basalt_deltas, nether, rain, spectator, teleport, warped_forest
20w15a
Retrieved
This happens too if you TP long distances in creative mode. I ran the command to get back to my portal, and for a brief moment while the chuck loaded, I saw rain falling.