One of the sacred tenets of climate change is that extreme weather is increasing. Is that really so?
Let us look at tornadoes. They occur when cold and hot air masses collide and in the fringes of hurricanes. Sometimes they can also be triggered by frontal thunderstorms. So if extreme weather increases by time, so should tornadoes, both in severity and numbers. Let us see if that is so.
So far this year, the number of tornadoes are slightly below normal:
If we look at “tornado alley”, the state of Oklahoma we see that there has been about the same number of tornadoes for the last 65 years
but 
but the number of strong tornadoes , F2, F3, F4 and f5 have been trending down for the same 65 years. How is this statistics holding up for U.S. as a whole?
Severe tornado trend is down:
And most significant of all, the worst tornadoes of all are declining. The last F5 tornado occurred in 2013!
Thanks to increased CO2, the poles are slightly less cold in the winter, while the temperatures at the equator are not changing with increased CO2, water vapor is the all dominant greenhouse gas, there is less temperature gradient between equator and poles, leading to less violent weather. While the number of tornadoes stay about constant, the number of strong tornadoes decrease. This is good news.
