Winter vacation

So i am Asian, haven't experienced winter yet coz where i live it's so tropical. I'll be in the States 2nd week of Feb. I'd go to Idaho, Minnesota & Kansas. Is it still so cold in those places next month? If so, you think i should bring very thick jacket and winter boots? I really don't have a lot of idea on how thick the clothes should i bring. I hope someone can give advice or post pictures of clothes i should be wearing. Thanks!!