There is no place that "doesn't get tornados" -- they have been recorded in every one of the 50 states in the US, and I suppose in the rest of the world. Of course they are more frequent in "Tornado Alley".
The number of reported tornados is higher in more densely populated areas. That is why Dallas/Ft. Worth and Oklahoma City/Tulsa appear like high-tornado islands on the map. The actual number of tornados is probably just as frequent in the rural areas in between, it's just that nobody reported those.
I grew up in Tulsa. The big danger there is complacency. The warnings are so frequent that people tend to start thinking the weather bureaus are crying wolf. The other dangers with severe t-storms are lightning strikes and flash floods. It is good advice to unplug electronics (not just turn off, unplug) and the land line phones.
The rule of thumb for how distant a lightning strike is is 5 seconds per mile. The speed of sound at sea level is approximately 1100 feet/second, so sound takes slightly less than 5 seconds to travel one mile (at 70 degrees). That's 344 meters per second, or about 3 seconds per kilometer, if you use the metric system. Sound travels slower at lower temperature, but the approximation is good enough. If there is no perceptible gap between the lightning and thunder then the lightning is quite close, probably within 100 yards. There is also an effect of "attenuation": higher frequency sound dies out sooner. Thus if you hear a high "crack" then the lightning is relatively close, whereas a long, low rolling rumble is distant.
As many people are killed by lightning as by tornados annually.
