For those of us with no real navigation experience, encountering longitude and latitude coordinates is usually the result of some hiccup using Google Maps. 40.722272, -73.994194?

Google Maps accepts latitude and longitude in any of the three common formats; use whichever one is most convenient: Degrees, minutes, and seconds (DMS): 34° 7' 8.904'' N 118° 18' 1.296'' W ...

I've seen lots of tornado maps and charts over the years, but these are the first ones I've seen that show the frequency of U.S. tornadoes by latitude and longitude lines.