Desert Storm started days before GHW Bush announced it. Saddam isn't so stupid as to think the President has to announce the war before it starts.
In Desert Storm, Saddam had a deadline. The war started within a day or two after the deadline passed. To preserve some surprise, they went right after the deadline, while sending signals that we were going to futz around for a few days.
Here, there's no deadline, and Saddam is not stupid enough to assume that we will announce the start time to him. However, he's going to be looking at Tuesday, Wednesday and Thursday this week as more likely start dates. I say go Monday night. Of course, I also said we should go last September, and Colin Powell has proven me right.