The United States far and away has the most tornadoes of any other nation in the world -- due to the unique terrain set up that sets up frequent clashes between cold, arctic air coming down from interior Canada mixing with the warm, moist air from the Gulf of Mexico, tossed together over flat terrain that allows air to flow freely.
John Nelson, with IDV Solutions, went through and made this great image montage that shows every twister that touched down since 1950 through 2011 and the path that the tornado took. The brighter the streak, the stronger the tornado.
Here is a zoomed in crop of the Pacific Northwest:
You can see the bright streak from the Vancouver, Washington tornado that killed 6 people in April of 1972. The bright spot near Seattle was the F3 tornado that struck the Kent Valley on Dec. 12, 1969 -- a very unusual tornado in its strength and time of year -- December tornadoes are exceedingly rare in the U.S., much less the Northwest.
This site will show all tornadoes that have struck Washington, and here is Oregon's.
For more ooh, and ahh, Nelson compiled an animation of tornadoes across the U.S. for each year:
Or for even more information, Nelson has also created an interactive database and map that will allow you zoom in and find out information on every tornado in his database.
Need more? Not to be outdone, Nelson also made a map of earthquakes since 1898.
"The result looks an awful lot like a fleet of Nickelodeon tankers spilled the world's supply of floam," he says.
Can you spot the Ring of Fire? Nelson says if you plotted each quake as a float, you could walk from Seattle to Wellington, New Zealand.
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