DW's and I little secret is to pack as much as 10 pair of shoes. A pair when it's sunny, a pair when a little rain is expected, a pair for heavy rain, a pair for the pool… you get the idea.
Nobody can control weather but AT LEAST we can pick the right shoes.
As other posters pointed out, you're going to WDW and you're going to enjoy it no matter the weather! Sit back, relax, and don't forget you can always buy more shoes at Disney Springs! (I know well: we'll have 11 pair of shoes on our journey home

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