Meaning?

[󠀡󠀡⁧⁧|​|]

How does the tornado / the deer / the double moon appear because some girl chanches time?
And what does the butterfly mean? (It seems to be important 'cause it apperars at the end again)

[Day Walker]

Messing with time caused a chain reaction as per warren and that butterfly is spirit animal of chloe

[talemore]

Why not download the directors comments or find it out on your own.
the doe is a spirtual creature of Rachel, the butterfly is a spirtual creature of chloe
The game calls it a tornado and some call it a hurricane because that's what it should had been if it wasn't a black hole. The vortex is the source of Max power and when it vanishes so does her powers (she's technically a sorcerer) The rewind symbol is a dreamcast who symbols that the game is within a dream. You can actually find this symbolism in movies for example Brazil where you see the symbol while the maincharacter has gone insane. The moon can be seen in the water reflection and when chloes boot touches the water it creates a reflection of two moons. Symbolic chloe doesn't care where her feet stomp as she doesn't care about the two moons. Mirrors have always been fascinating vanities and described as another world but there's a natural explanation that light was bend to create the illusion of two moons.
The butterfly is a symbolism of a theory within the chaos theory, you can say it's a standalone theory who works with the chaos theory where chaos has a pattern who looks like a butterfly.

The least complicated way to describe it is that the game is a different version of the movie" the butterfly effect" as both characters in the movie and life is strange gets nose bleeds for no physical explanation.