Randy Jennings
Supporter
- Joined
- May 18, 2013
- Messages
- 826
Since it was 104 in Dallas today, I've turned my thoughts to cooler weather. With El Nino expected to be around and even strengthen thru the fall and winter, I found myself starting to get hopeful for a chance to chase this fall or winter. Sure it will not be like the spring, but with that jet likely setting up across the southern US, a chaser in Texas can dream, right? So I started to do some research to see what the data said. There has been a lot of good posts on Stormtrack about ENSO and tornados, but most seem to focus on the spring season. I found a couple of good sources of information I figured I would share. The first covers the entire year: http://www.spc.noaa.gov/wcm/enso/. The second is a paper written by Cook and Schaefer called "The Relation of El Niño–Southern Oscillation (ENSO) to Winter Tornado Outbreaks" at http://www.spc.noaa.gov/publications/cook/enso-mwr.pdf .
The Cook/Schaefer paper is very well written. I encourage you to read it for yourself, but here is a summary: As expected, they conclude that ENSO makes a difference as to where tornados occur during winter. They also note that tornados are more frequent during neutral phases and that stronger long track tornados are statistically more likely to occur during La Nina and neutral winters than in El Nino winters.
The Cook/Schaefer paper concludes with a reminder that ENSO phase by itself can't be used as a tornado forecast tool. They remind us about the March 1998 Minnesota outbreak in a El Nino year when the climatologically preferred area for tornado activity was the Gulf Coast area.
The Cook/Schaefer paper is very well written. I encourage you to read it for yourself, but here is a summary: As expected, they conclude that ENSO makes a difference as to where tornados occur during winter. They also note that tornados are more frequent during neutral phases and that stronger long track tornados are statistically more likely to occur during La Nina and neutral winters than in El Nino winters.
The Cook/Schaefer paper concludes with a reminder that ENSO phase by itself can't be used as a tornado forecast tool. They remind us about the March 1998 Minnesota outbreak in a El Nino year when the climatologically preferred area for tornado activity was the Gulf Coast area.
