Hi! It does tend to be a bit rainy during August. However, in 2002, we went for 9 days at the end of August and I do not think it rained more than one day and it did not spoil our plans at all. This past August 2003, however, we went the same time and it rained atleast four or five days. Some days the rain lasted for a couple of hours, heavy with lightning and of course, we could not use the pool during those times. We still had a great trip though despite the rain. From what I hear, we lucked out with the great weather we had in 2002. August does tend to be rainy and very humid. We too usually need to vacation the end of August and will continue to visit Disney then so even though it can be a rainy time of year, I would not let that stop you. There are still so many things to do inside at WDW if it should rain for a couple of hours. Also, the crowds are a little less at the end of August because some schools are back in session. That makes it more pleasant.
Congratulations and Welcome Home!!