If you turn off the clouds when you are seeing them, they will stick to the camera statically instead of disappearing. They won't disappear unless you turn them back on. Leaving the world does not work. The clouds will stay even when you enter another world or server.

How to recreate:

1. Go to Options, Video settings, Clouds and set them to "Fast" or "Fancy"
2. Look at the clouds.
3. Go to Options, Video settings, Clouds and set them to "OFF"
4. You will notice that the clouds remain and move with the camera.