I just returned to Tinker with one of our E-6's from a weather divert overnight down to Houston...
cezzna, much like your idea that people should be encouraged to leave at the first sign of a good possibility of something happening, my command attempts to predict the future and prevent damage to our aircraft when we can't get them in hangers due to lack of space.
9 times out of 10 however, when we take the planes somewhere else, nothing happens. Same thing last night. Doom and gloom, possible tornado outbreaks, pretty good chance of baseball size hail... We go spend the night somewhere and Tinker gets some light ice from freezing rain.
Running from tornadoes, that DON'T exist yet, due to a warning is a complete waste of time for the everyday person. Yes, tornadoes have the potential to kill people when they strike. So do drunk drivers, mentally unstable people with AR-15's, and many other things in the world. All of these things can and WILL happen at one point or another and we, as humans, can do nothing that will prevent them all.
The weather forecasts we have now are great for warning people of the potential damage... Until they can forecast the EXACT line that a tornado is going to come down, at least a few hours before it happening, there is no reason for people to run for the hills. For all you know, the people will move out of their home that won't get touched and move into the building that is demolished by the F5 blowing through.