Yep, frankly, I think in over 40 years of going during just about every month of the year, I've only had about 3 trips where it didn't rain at least one day. Sept. is hurricane season so you are just about guaranteed to have at least an afternoon shower. Could be a quick 10 min. semi-light rain, could be a 30 min. gully washer, could be a couple of hours yucky rain, could be a most of the day rain. You never know. I never go to the parks without at least a cheap poncho that can fit in a pocket. I'll be there Sep. 13 - 19 and will be taking a few cheap ponchos, a Disney heavier poncho, a rain jacket and an umbrella. I just depends on what the weather forecast looks like on the day as to what I actually take into the parks. I also take a wet bag to fold my poncho/rain jacket/umbrella into after use so it doesn't drip all over me or my bag.