Hot and humid weather will continue through this week and into Friday, with mostly sunny skies and high temperatures in the lower 90s. The afternoon dewpoints will be in the lower 70s, which will put the heat index near 100 degrees.
On Saturday a cold front will move across the area from north to south. As it does, it may spark off a few showers and thunderstorms across north Georgia. Coverage should be fairly isolated, and and showers should be short-lived, so I expect that any potential impacts on the racing will be low. The afternoon hours will be the most likely time frame for potential showers and thunderstorms.
The main change in the forecast is for Sunday, as it now appears likely that the front will push well to the south and west of Road Atlanta, and high pressure will build into the area more aggressively than previously shown by the models. The result of this will be a very pleasant day on Sunday, with cooler temperatures and lower humidity. Showers should stay well south of the track closer to the front.
I plan to have another update posted on Friday.