We were there last september, and we caught the tail end of tropical storm Fay, it wasn`t quite a hurricane.
Anyway we had a few really great days, some slightly overcast days and more rain in 3 days than I have ever seen.
On the rainy days we did what what all self respecting disney holiday makers do, we bought ponchos and got drenched walking round the parks.
Its a hit or miss with the wather at that time of the year, but last year didn`t put us off cause we`re going back this september.
EDIT %% sorry DW has just informed me we were away in August last year not September. My memory is getting worse.