Steps to reproduce this issue:
Find a biome that can rain next to a biome that can’t rain.
/weather rain
Go form the raining raining to the dry biome.
Wait for the biome effect to change.
Expected result:
It wouldn’t take that long to change the color of the sky and sand blocks.
Actual result:
It takes too long.
Additional issue:
Standing between these two biome will make the whole desert look yellow.
And for when going from dry biome to raining biome, you can see that the sky becomes clear at first, and then the fog appears.
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