re: A map of every tornado emergency ever issued

Also, terrain and the ability to get eyes on a tornado makes a huge difference. Out west they have low-precip supercells that put down easy to spot and track tornadoes. Hell, they regularly use helicopters to track tornadoes. With the high-precip storms we have, and the trees, and the hills and hollers, and the creeks and rivers, it is infinitely harder to confirm a tornado on the ground. So if there was a confirmed tornado doing damage in a rural area, and it is headed towards a populated area but they've lost visual they will, out of an abundance of caution, issue the warning with a Tornado Emergency tag. It is the best approach.