Greetings Southern Kentucky!
September 7, 2018 is looking to be the start to a wet weekend. As remnants of Tropical Depression Gordon moves North-Easterly across the plains and a weak surface boundary sitting over southern Illinois and central Indiana. This adds up to a nice set up of convergence, giving Kentucky a chance to see pop up storms. The greater chance for the convergence to trigger pop up storms is southern Indiana and northern Kentucky. Whereas in Southern Kentucky will start with to isolated showers to scattered in the late afternoon hours.
Below is the 11Z HRRR at 2 p.m Central Daylight Time
http://weather.cod.edu/forecast/
As the HRRR indicates that the chance for pop up storms will be greater in the late afternoon. With a low chance to see isolated thunderstorms in the evening hours. The overnight hours looks to be quite, but can’t rule out a shower totally.
The temperatures looks to be similar compared to early week. With the high around upper 80s with high dew points in the low 70s. The rule of thumb says that when the dew points are in the 70s that it feels oppressive and you will probably feel awful, even if you have to be outside for just a short amount of time.
The 11Z HRRR is indicating dew points in the low 70s in central Kentucky.
http://weather.cod.edu/forecast/
Clouds will increase though out the day and with the chance of scattered showers and thunderstorms the low is looking to be in the mid 70s.
The current cloud cover is broken and will stay broken till the late afternoon to the evening hours where then it will switch to overcast. 
https://www.spc.noaa.gov/exper/mesoanalysis/new/viewsector.php?sector=19#
In summary:
Friday: Highs in the upper 80s with lows in the mid 70s. With increasing clouds and precipitation in the late afternoon and evening hours.
Saturday: Highs in the mid 80s with lows in the lower 70s. With a greater chance of showers and thunderstorms in the afternoon.
Sunday: Highs in the low 80s and lows being in the upper 60s. with chance of showers throughout the day and will clear out sometime through the overnight.
The beginning of next week looks to be in the low 80s as a high and a small chance of precipitation.