El Niño and Oklahoma tornado season
A closer look at past events
After a strong El Niño, there appears to be a bias for Oklahoma to have an above-average tornado season.
An El Niño is a planetary weather event, when ocean waters in the eastern Pacific warm to above-average values. This in turn, causes a persistent Pacific jet stream across the southern U.S. during the winter months, producing cool and wet conditions.
During the spring and summer, the affects of El Niño are less and the current phase of the El Niño appears to be weakening, but there appears to be a bias for Oklahoma to have an above -average tornado season after a very strong El Niño.
Compared to this year, other very strong El Niño years include 1972-73, 1982-83 and 1997-98. Each of those years, Oklahoma had above-average tornadoes. From 1950 to 2014, Oklahoma will average 54 tornadoes a year. During those very strong El Niño years, tornado totals include:
- 1973, 76 tornadoes
- 1983, 92 tornadoes
- 1998, 83 tornadoes
Click the image above to take a closer look at the very strong El Niño years and total annual tornadoes in Oklahoma.
When you break down each tornado season in Oklahoma after a strong El Niño, each June had above-average tornado totals. During an average June, Oklahoma will see about 8 tornadoes. During those three very strong El Niño events, each June had 24, 23 and 22 tornadoes respectively.
Based on this information, one could conclude that this tornado season across Oklahoma should be above-average, or at least a late season, but this is a very small sample set.