Just got back on Saturday and, as this had been the first time that we had gone during the summer months, we were worried about the rain.
It rained almost everyday, but mostly it did not arrive until after 3pm. Some days it set in for the rest of the day, but didn't spoil the enjoyment of the holiday. We got to the parks early and had done most rides before the rain came on.
The local news channels reported that it was the 2nd wettest June on record - over 17.5inches fell in Orlando - certainly didn't put me off going back again.
Don't worry - you will have a great holiday no matter what the weather does!