Good Morning James, 

Thank you for contacting the U of M Extension Service. 

I am not sure what you are saying about the location of the tree. If the tree is in a location where it has not been watered over the past drought, the tree may be reacting to the drought. It was hard on trees and they are slow to react. 

Please click on the following link about oak wilt: https://extension.umn.edu/plant-diseases/oak-wilt-minnesota

Here is another link about white oak and the potential diseases: https://trees.umn.edu/white-oak-quercus-alba

Good Luck!