Madison Area Science and Technology has a spotter course online.

May 1, 2004
Springfield, IL
Hey George, I went through your presentations. Nice job assembling those and making them available. Some audio with them would be great too. I was wondering if you could expand upon this quote from the Tornadoes lesson:

The most likely region of a thunderstorm for tornado formation and development is in the updraft region, but only if there is a good source of warm and moist inflow.
Wouldn't all tornadoes form in the updraft region, since they're all driven by an updraft? You go on to talk about tornadoes forming along convergence zones, which I assume are spouts, but these too are still being stretched by an updraft. Was just looking for some clarification there. Thanks!