Jail is quite probable, but not with all judges. You need to contact a lawyer who is familiar with your judge. See http://www.colorado-dui.com/states/Pennsylvania/reading-dui.html
You face two potential prison terms one would be if a detainer is lodged against you by your probation officer as the arrest would no doubt be considered a violation of your probation. The time spent in jail for that could potentially be much longer than if convicted of the DUI.
With regard to the DUI you are just at the cusp of the no jail - No Licenses suspension / Jail license -suspension line due to the level of your BAC. Unfortunately you are on the side of the line that calls for jail and a license suspension. However you are so close that there may be a good chance that you could be pushed back to the other side of the line.
The sooner you contact a qualified attorney the better.