I have limited experience with the S.Holston-unfortunately...So, I would be guessing on why you are seeing any changes.
Some tips to help you analyze your hypothesis:
-Review climate pattern for the past 5yrs and put it in a spreadsheet for analysis. You might find some things that jump out.
“Every human has four endowments- self awareness, conscience, independent will, & creative imagination.
These give us the ultimate human freedom... The power to choose, to respond, to change.”