The models have not done a great job with how they handle a cold front that moves southward through Virginia and North Carolina this weekend. This makes for an uncertain forecast. What I am confident about is that temperatures on Friday will be hot, with highs in the mid 90s and a heat index around 100 to 105. Most of the day will be dry, but there is a slight chance of showers and storms moving into the area late in the day, mainly after 5 pm.
A weak front or low pressure trough will be associated with these showers, and will move through in the evening hours. It will shift winds to the north, and bring slightly lower humidity for Saturday. There will still be some instability in the afternoon that may allow for isolated showers and storms to develop. Again, most of the day will be dry, with only a small chance of showers late in the afternoon.
Another front moves in from the north on Sunday, and may initiate showers and thunderstorms in the afternoon. With more cloud cover, temperatures will be cooler, in the 80s.