Hi d4ry1,
Rafeeq is correct, unfortunately there is no Notification Condition for what you are trying to do :(
Maybe the closest you might be able to get is using Scheduled Reports with a Report Type of "Scan Report", and a Selected Report of "Computers Not Scanned" or "Computers by Last Scan Time".
Although it is after the fact, rather than immediate as with the notification, if you know roughly how long your scheduled scan runs you could schedule one of the above reports after the scans are done.
Hope this gives you some ideas.
Steve