What type of luggage do you bring to Nebraska for about a month?

I've never been to Nebraska and this is only a maybe trip because my friend's sis doesn't want to go to Nebraska this time so my friend is going to see if I can come with her in place of her sis because she doesn't want to go alone, so if I do go I really wanna know what to bring and what not to for about a month. Does it get really hot in Nebraska or is it like in deserts where it's hot in the day but cold at night, and does it rain often. Also I need to the average humidity is because my hair frizzes in high humidity and I don't want to go Bride of Frankenstein. And any other info that could be useful, and where to get good luggage because right now I'm going to have to bring a lot backpacks unless I get a new suitcase.