Weather radar, like our number one tool for observing storms, it just can't see tornadoes. One part of the problem is like it basically picks up on moisture rain and you can infer things from rain but it's an incomplete picture in a storm. The other problem with radar is physically radar is this dish that spins. And so every time it spins, it takes an observation of the thing that it's observing,. But that takes a few moments for it to spin. You can have a big lazy vortex in one scan and by the time the radar swings around again, you've got a tornado.