i think a fine mist of water like you would get off a i/c spray unit from a scooby etc wouldn't plummet oil temperatures if you use it when it gets hot. all it would do is increase the thermal conduction between the air and the cooler, which would be a good thing in this case.
plus with temps of 100degrees any excess water will be vapourised into steam and make SFA difference in terms of getting water on the track etc.