hi
i have been to wdw 2 times in september and we had a few showers whilst there, and when it rains it rains, but like the other threads say it is quite good fun, plus the parks seem to become quieter, when it stops raining and the sun comes out it does not take long for the rain to go, we are also going next september. you can buy the ponchos (as we did), we have quite a collection of them now.
regards
nilrs