Current tornado numbers (adjusted) are well below normal in 2013. via Storm Prediction Center
Strong EF-4 tornadoes peaked in 1974. They have shown a general decreasing trend since then (via Paul Homewood, Not A Lot of People Know That)
EF-5 tornadoes occurances show a declining trend since the 1970's. (Paul Homewood, Not a Lot of People Know That)
CLEVELAND - Where are the tornadoes?
Not that anyone is complaining. This year (2013) is on track to see the least amount of twisters in the modern record.
We've talked about the record low amounts of strong tornadoes so far this year. Strong tornadoes are EF-3 strength or higher.
Look at the graph from the Storm Prediction Center below.
Current adjusted totals for the U.S. stand at 621 twisters in 2013. The previous low for Sept 17 was 709.
The average number of tornadoes by mid-September would be up around 1,200. The modern record for tornadoes goes back to the early 1950s.
We can also break down the decline in tornadoes further. The strongest tornadoes are EF-4 and EF-5. EF-5 twisters can have winds well above 200 mph.
Graphing those tornadoes tell a similar story. Take a look at the number of EF-4 tornadoes with winds speeds between 166 and 200 mph since 1970.
These numbers are declining!
EF-5 tornadoes have winds above 200 mph. They cause the worst damage of any tornado.
Historically, as the graph shows, those numbers are also showing a decreasing trend.