Natural reducation of Tornadoes? When and How does this work?

I understand that when certain climate patterns occur we will get
either wetter/drier or colder/hotter seasons. BUT, is there a
particular pattern in our climate that seems to give a hint at the
number of tornadoes for future years?

El Nino and La Nina both are talked about a lot as causing changes in
weather patterns. I guess what I am asking is, are their certain
climate patterns which give a good idea of the coming Tornado
potential?

If this pattern does exist, could some please discuss it here or
provide me with a link that talks about it?

Also, I have noticed that the average is 1200 per year but some years
have far more and some far far fewer than that number. There must be
something in our climate that is causing this. I really wish I knew
what that was so I could get a gauge on what to expect.

As a side note, if the pattern for frequency of tornadoes continues in
2006 I would image the number would end up going well above 1200.
Probably 1500+

Please help me with this information if you can.

Many Many Thanks,
bob

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