Jun 28, 2016

Big Tornado Season Next Year?

The number of tornadoes in the US has been below normal for the last 5 years:
El Nino is gone. Over the last two months, sea surface temperatures have been below normal in the central equatorial Pacific. Trade winds have been above normal across most of the Pacific for the last week. It is likely that La Nina will emerge sometime later this year.

4 out of the last 5 years with tornado counts being more than 1 standard deviation above normal have been during or immediately following a transition from El Nino to La Nina (1998, 1999, 2008, 2011):

Three of these years (1999, 2008, 2011) had well above the normal number of strong tornadoes.