At today's briefing NASA managers indicated that there were no technical issues precluding Discovery from launching Wednesday afternoon at this time. After a weekend of repairs everything is proceeding smoothly with the countdown. Weather on the other hand could be an issue.
The weather forecast for a Wednesday launch still appears to be good with a 30% chance of violating the constraints for launch. However there is the possibility of a greater chance of rain and even thunderstorms. NASA will have a better idea tomorrow how the weather will pay out. What we do know is that the weather forecast for Thursday is bad with a 60% chance violating launch constraints. Friday it goes back to 30%. While NASA is tracking tropical storm Tomas, that storm is not an issue for a Wednesday launch.
NASA is also considering extending the launch window another day to Monday should it look it might be necessary. The Orbiter Team is examining that issue to see if it's possible according to Mike Moses, Chair, Prelaunch Mission Management Team.