What if sonic gets zapped while doing the dance.......
I don't know why but I just thought of this idea where Sonic helps Tails overcome his fear of lightning by taking him out into a rainstorm and performing the song "Singing in the Rain" for him, even doing the whole tap-dancing with the umbrella and everything.
The fear of lightning won't ever fully go away, it's a phobia, just as Sonic's aversion and fear to deep water bodies.
But this little moment of joy, the silliness and laughter when the storm calms to a soft tranquil drizzle, the taps and splashes.. it makes the associated fear and aversion to rainstorms go away. His fur no longer stands on end by the pitter patter of raindrops in the absence of lightning and thunder