Rain falls over parts of badlands biomes

While exploring a badlands biome, I noticed that rain would fall over parts of it but not over other parts of it. I suspect this may be because there is a large dripstone cave biome under the badlands, but there are other parts of the badlands that are over dripstone caves but don't receive rain.

 

To reproduce:

1. Create a default world with the seed -1210834265145960263
2. Run "/gamemode spectator" and "/weather rain"
3. Run "/teleport @s 1520 70 -1520"
4. Despite being a wooded badlands biome, it rains over this block.

As stated earlier, this might be because there is a dripstone cave biome below the block. However, if this procedure is repeated, except that you run "/teleport @s 1570 140 -1520" instead of "/teleport @s 1520 70 -1520" in step 3, then the block you are over will be a badlands biome and will not receive rain, despite there being a dripstone cave biome underneath. This means that the rain may not be related to the dripstone caves.