Relative directional teleportation of throw-able entity's has broken

I recently worked on a minigame that requires teleporting an arrow in the direction its facing, after it has been summoned or shot from a bow i use this command /execute @e[type=arrow] ~~~ tp ^^^1 however it does not teleport it in the direction it's facing, rather it teleports relative to it's positioning in the world using ~~~. this also applies to snowballs.