MLP FiM My Little Pony Friendship is Magic
S05E05 S05 E05 Season 5 Episode 05 Tanks for the Memories
Rainbow Dash - I just have to stop winter!

Every pony down in Ponyville liked winter a lot, but Rainbow Dash, who lived just above Ponyville, did not.
Dash hated winter, the whole entire season. Don't ask me why, no pony quite knows the reason.
It could be because she hated the chill in the night.
It could be, perhaps, that her winter clothes never fit her right.
But I think the reason that holds the most rank was that it was the hibernation period of her pet tortoise Tank.
But whatever the reason, her clothes or her pet, she plainly did not want the season to arrive just yet.