The El Nino year of 1983 ranked second with 20 storms, and the La Nina year of 1971 ranked third with 18 storms. While in some years El Nino might set the stage for more strong and violent tornadoes than normal, the relationship is not strong enough to say that an El Nino will bring more strong tornado activity than normal to Florida. There are some indications of a weak signal with F2 and greater tornadoes over Florida and with the ACF over tornado alley. Perhaps if one subdivided either the time window, or the areas considered some statistically significant correlations might be obtained. However, with only 10 El Ninos and 8 La Ninas over the 47 years of this study, the data is rather sparse.
Tornadoes are even rarer.
If the regions of study become too small, the validity of the study would be dubious no matter how great the statistical significance. To examine this possibility, monthly values of various tornado parameters over the four areas presented in this paper were compiled. By assuming that tornado activity in A given month is independent of that in months, the 47-year time series from each month can be detrended with a least squares fit. Plots in the form of bar graphs with superposed best fit curve were created. Several will be presented at the conference, but there simply is not enough room to show one in this preprint.