Can't answer your actual question, since I don't have the required encyclopedic knowledge of the 3.5 spell system, but I want to point out again, for the record, that it is already a stretch to assume MitD cause the first downpour (although that one could easily be explained by Control Weather).
It is even a larger stretch to posit that MitD caused the second downpour. The cutaway shows the downpour already in process, and a quite happily sleeping O-Chul, unlike the first time when it is suggested that MitD causes the rain because O-Chul is starting to feel sleepy. Add to that the distance and uncertain location (even if the cloister wasn't in the way), and I doubt anything short of Wish can actually explain it, unless we also add a number of supporting spells to extend range of casting and determine location.
Grey Wolf