I have been analyzing my Rainwise MK III temperature graphs since I moved the unit from the peak of the roof where it was hard to service to the eve where I can get at it from my ladder. I noticed a dip in temperature each day at around 4pm, increasing about 2 degrees by about 4:30. I guessed shade, and sure enough, I checked it today and the drop occurred as the sun passed behind a large white pine. Obviously this spike will change with the seasons, but is a 2 degree difference between light and shade an acceptable difference in value? It's not like I can do much about it, I live among trees and Rainwise does not offer fan aspiration.