That may have been my post. It's not rain as much as a thunderstorm- which is pretty common at WDW in the summer.
In thunder all the animal attractions close, Kali, EE, Primeval Whirl, the bird show, and I think Triceratops Spin, and the Boneyard (not sure).
The indoor shows still go on, but you still have to wait outside for them- and they get popular.
When planning summer trips, I try to make my AK day flexible- er, swappable- with at least one other day. Simply put that means two days where I have our TS dinner booked at a resort that's convenient - like our home resort. We nealry alsways do on TS dinner each day. If you are QS eaters, than swapping is even easier.
It's also very easy to park hop if you have hopper passes.
Even with that, often the thunderstorms don't happen until 3pm+, it's possible to cover all the biggies at AK by 3pm.
Kali is kind of fun in the rain. The only part that's not fun is if you hop on the bus back to your resort soaking wet. (leaving right after Kali)