What I expected to happen was...:
The particles to appear above the ocean

What actually happened was...:
The particles were layered under the ocean as shown in the gif below

Steps to Reproduce:
1. Throw a Lingering Potion on a single block in the air above the ocean
2. Watch

Due to the size of the created gif I was unable to upload it here.
Here is an external provider(gfycat) containing the gif: http://gfycat.com/SnivelingRapidIcelandicsheepdog