To say the Thursday night through Saturday forecast is uncertain is a bit of an understatement. The forecast from yesterday is quite a bit different today. Even with that change, the spread among our different computer models remains quite large!
One way to view the uncertainty in the forecast is to use ensembles. Basically one computer model is run 20 different times with slightly different tweaks to represent a range in plausible scenarios. When all 20 show the same thing you can assume the forecast is high confidence and when all 20 are all over the place you can assume forecast confidence is low.
So what will happen? Right now we've put a chance for showers in the forecast Thursday afternoon through Friday morning with one system moving in and then a second round of showers Saturday night. If we can time everything out we'll salvage a mainly dry Friday (day) and Saturday (day).