May 31, 2013 El Reno Tornado

Apr 10, 2008
Tulsa, OK
I am working on some research for the 2013 El Reno tornado and have come across some interesting tidbits of data surrounding some of the specifics with regards to Twistex's fateful impact with the sub-vortex.

Several years ago while going through countless videos on YouTube I came across Jim Bishop's footage shot from I-40 where you see the headlights of Dan Robinson and Twistex as the powerful sub-vortex bears down on them. Their (Bishop's) view is cut off by the Radio Road overpass and once they re-establish their view of the tornado east of Radio Road, the tornado has morphed into a maxi wedge and neither Robinson's or Twistex's headlights are seen again.

Here is a link to the video:

I spent some time looking at the location on Google Earth and even visited the location on two separate occasions and can confirm that you can see vehicle headlights on Reuter Road from I-40 where the video was shot.

There was some speculation that perhaps the headlights were not of Robinson and Samaras, but were of Piotrowski and Marshall who were on Jensen. however, after reviewing both of their videos, the angles don't match up with the Bishop video.

More recently I found a Reddit thread where someone had done a few calculations from the Bishop video and came up with the same results:

Something I find interesting is most research papers and the general consensus is that Twistex was overtaken by the sub-vortex at roughly 23:23-23:24z (6:23-6:24pm) while the Jim Bishop video when compared to synced video found at: El Reno TED suggests Twistex was overtaken by the sub-vortex between 23:21:30-23:22:00z (6:21:30-6;22pm), or a full 1 to 2 minutes before what has been suggested in various research papers and official statements. I am curious if anyone has any thoughts on this.

Something else I found of interest is the evolution of the wall cloud/SVC (streamwise vorticity current) during the life cycle of the El Reno tornado. Initially, the El Reno tornado formed under a distinct wall cloud with a tail cloud/SVC extending to the north. During the first half of the tornado (west of HWY81), the tornado shifted southeast, away from the SVC, as the hook "uncoiled". A large precip core develop around the north side of the tornado and appeared to separate the tornado from the SVC as it approached HWY 81. Check out this incredible footage from Brenden Lindsey as he raced south to stay ahead of the tornado as it approached 81. He had a perfect view of this exact evolution.

Is it possible that the density current from this precip core, as it rotated cyclonically around the north, then west side of the tornado, shoved it east across HWY 81 causing it to accelerate?

East of HWY 81 the main sub-vortex began to turn left to the northeast and merged back into the wall cloud/SVC. The hook recoiled to the north. Perhaps the intense low-level updraft with the SVC acted like a giant vacuum and pulled the sub-vortex into it in a prolate cycloid looping motion. Twistex was under the SVC which is why they weren't experiencing any rain, and could be why Tim commented that they were in a bad spot.

Anyway, these are a few observations I have made from researching this tornado. Please share your thoughts and questions. I would love to get more discussion going about this tornado, especially with the 10 year anniversary coming up next year.
At around 3:43 in Brendon's video, I noticed what appeared to be a satellite tornado which got absorbed into the main circulation as it maxed out. Curious question, at one point do we consider it a "satellite tornado" versus being a sub-vortex of the entire tornado cyclone itself here (not at all questioning the science, I'm genuinely curious as these particular vortices looked very large compared to typical sub-vortices).

I don't have anything to base this off of, but I feel like some of the sub-vortexes on the El Reno, OK 31 May 2013 event could be considered satellite tornadoes of their own (similar to what occurred with the 04 May 2007 Greensburg, KS event)....versus a subvortex of the parent wedge tornado.

I ask this because I have seen other storms, where tornadoes have formed in the SVC or around the backside and then get absorbed into the main tornado...and this process continue to repeat itself. What makes this interesting to me is that dense precipitation curtain obscuring the view of the main circulation. Other storms that have shown this behavior (Pilger '14, DDC '16, Albert Lea '10, Dupree SD '10) have all been pretty visible or rain free.

I did not chase this particular event in OK but instead IL/MO near STL where I observe a wedge tornado, so I can't offer any personal insight into the situation itself in Central OK that day, except for the video I've seen on YT or here.

I don't know if he is on here, but Gene Moore has some excellent stills from the same area as Jim Bishop and Simon Brewer off the interstate where it maxed out to its full width. He has discussed his thoughts on Facebook about the tornado itself and has similar beliefs that some were actual satellite tornadoes versus sub-vortices. I will leave it at that though to avoid speaking for him more. However again, this is really just all hearsay as we can't say for 100% certainty. The atmosphere really knows no bounds and our human definitions of certain scientific events can be quite ambiguous and leave gray cracks for certain things.
It's not uncommon for tornadoes to accelerate as occlusion occurs, so that in and of itself isn't particularly noteworthy. Had it been a mile wide or an otherwise more "normal" size for a wedge, I'm not sure we would consider it all that out of the ordinary. Granted, that's my opinion, and I'm sure others will think differently, but that's my thinking as someone who's been chasing since the mid 2000s, and was following weather for a good decade before that.

To Ethan's question about sub-vortex vs satellite tornado, I really think it boils down to whether it's within, or outside, of the boundaries of what we're deeming the parent tornado to be. As far as the HP nature of the storm vs others showing a similar behavior, I think that really boils down to moisture aloft (or lack thereof) and the discrete nature of days like Pilger, vs El Reno looking more like a tail end charlie. It's been long enough since I've looked at upper air maps that I don't remember what the upper levels looked like on those days, but I suspect Pilger had stronger flow in the 500-700 range to facilitate venting. I doubt that DDC had dews nearly as high as El Reno or Pilger, but without looking at the data, I'm guessing both DDC and Pilger had at least some dry air aloft as well. Pilger almost certainly as it was a very discrete storm. From what I recall about El Reno (I did not chase that day as I was on duty with my Reserve unit), there was very little capping and a ton of forcing due to the surface low, whereas (if memory serves) DDC and Pilger utilized boundaries from morning convection as their forcing mechanism, which was much more subtle than the surface low that El Reno had to work with.
I found another video that might help illuminate this situation a bit, one that I had not viewed before. From 9:12 onward it gets pretty interesting. You can see how fast the tornado goes from multiple vortex to wedge and then breaks down again into multiple vortices before a huge dense curtain of precipitation obscures most of the tornado cyclone. Around 11:55 mark, you can see the tornado re-emerge again from that dense precipitation core as a large wedge with rotating vortices around it. It then appears to get cloaked in heavy precipitation again and then is visualized again toward the end as the giant wedge with subvortices similar to Skip Talbot's video. The vortices on the outer edge are interesting to me. I'm just assuming it is because as noted above by Drew, that it could be the high RH value of the inflow parcels to the storm making every wisp of vorticity visible to the naked eye. I seem to remember observations that day running with temps in the mid-upper 80s and dews in the upper 70s in that localized area W of OKC with high CAPE/shear leading to a maxed out STP.

Another added note: It appears the storm chaser here is positioned in the RFD portion of the storm just to the W of the tornado. This would typically be a risky manuevur, but looking at the track of this particular tornado, it actually may have been a safer position than in clear air to the S or E of the storm given its dramatic shift in track. Just an observation though. I don't think one should take this as gospel though as other storms anchored on boundaries with high CAPE/shear combinations have swung back west or moved slowly that they retrograded westward (Bennington '13, Coleridge '14 examples).

Here is the video:
Each of the sub-vorticies of the El Reno were exactly that, sub-vorticies and not satellite tornadoes. Only one satellite tornado occurred, and that was an anti-cyclonic tornado southeast of the main tornado. Each one of the sub-vorticies of the El Reno tornado formed within the MVMC (multi-vortex mesocyclone) and were just part of the SVC process. In this case, the extreme environmental conditions created an exceptionally large MVMC that was very efficient at creating intermittent "parades of vorticies" that exhibited abnormally large sub-vorticies.

I can see how it would be confusing, even when watching the video. The sub-vortex which impacted the Twistex team was particularly exceptional in size and duration. I argue that the behavior/evolution of the El Reno tornado was more erratic and unpredictable than most tornadoes, although not unprecedented by any means.
Sorry for bringing up an older thread, but I've had trouble loading the El Reno TED page, or rather getting the videos to load with the map. Has anyone else had this issue? I am guessing the site might not be fully maintained today?
As I was looking back at some these posts, I went to Google Maps to re-orient myself to certain roads, and saw that the TWISTEX memorial is shown. This has probably been the case for quite some time and I just hadn’t had occasion to notice. A number of pictures of the memorial are posted on Google Maps. There are plaques commemorating Tim, Carl and Paul, and a plaque explaining how TWISTEX came to be. However, I did not see any narrative explaining what happened there, or mentioning the tornado. Obviously any one of us going to the memorial knows the background of the tragedy. But wouldn’t that be something important to include for the average passerby, and for general posterity? Anybody know why there is no mention of the incident, or the tornado itself? I assume it was an intentional decision to omit it from the memorial and not just an oversight... I am curious as to the thinking behind it.
Man, I keep going through everything I can find on the El Reno tornado (videos, research papers, interviews, literature, etc) and I have to say I am now at the point I am ready to retract my original statement that I believed the headlights belonged to Twistex. I had to put my own timeline together based on all the video and info I had because I couldn't sort though all the info, and I believe the headlights are most likely that of Tim Marshall. I recently found a longer cut of Tim Marshall's video I had not seen before that suggests he was pretty much in line with Jim Bishop's shot. The Jim Bishop video isn't time stamped correctly so it was a bit more difficult to determine the exact time of the headlights. I just want to make this correction, because I believe this now to be true, and I do not want to perpetuate any false rumors surrounding Twistex. I have always been curious about their final moments and I guess I was hoping to find maybe a new fact that could satisfy my curiosity and give me "closure" to this tragedy, but now I have come to the realization that everything we already know is probably all we will ever know.
While I had other motivating factors that propelled me down the never ending rabbit hole that is weather forecasting, this tornado is the primary cause of my intensifying fascination with tornadoes themselves. Initially driven by the sheer number of videos, I found it quite amazing to see the same event from so many different perspectives. The way the event unfolded, and the close to home tragedy at the end only added to weight of it's importance.

One of the research papers I had read concerning radar interpretation of the sub-vortex that struck TWISTEX, and it's behavior prior to that impact is freaky. If I understood it properly and remember correctly, it rotated around the circulation and then became stationary not far in front of the TWISTEX vehicle. After a short period of time, it made a small loop and went straight for them, almost as if it was sentient. The whole ordeal that so many chasers faced that day is humbling to say the least.

Like @Jamie H, I too noticed the TED page was non functional a while back, also assuming it was not maintained. I know it would probably be a considerable effort, but I always thought it would be incredible to analyze other significant events through that program if nothing else but for curiosity's sake.

While on the subject of El Reno videos, does anyone know if Dan Robinson is still a member here? I know there was disagreement back in one of the Covid threads. If not, it would be unfortunate considering his contributions to the forum. Not to get too far off topic, but does anyone know the significance of certain user names being a different color and "unclickable"... does that indicate they're no longer members?
This tragic event should not pass without serving a purpose. That purpose is teaching chasers a critical lesson: Don't chase from the front quadrant of a large, dynamic, HP supercell with heavy precipitation and very limited viability. Nor is it a good thing to go around bragging about how close you got when others died, although some early comments on video were without this knowledge.

We stayed at the Holiday Inn Express in Yukon, OK the night before this event, and decided early on that any intercept (based on upper air forecasts), would include HP precautions, so we would approach from the south. We were also concerned about traffic near OKC, which turned out to be correct, as pathways leading south from the storm were clogged with chasers, lunatics, frightened people and combinations of these.

Four people died on this day, and it's only a miracle the death toll was not higher, given TWC and others only surived by the narrowest of margins.