2014-6-16 MISC: NE/IA/IL/WI/MN

[Mark Ellinwood]

While I could certainly believe the third dust-up is a tornado, I'm not 100% convinced. Would have been nice to have a steadier+longer shot of it to see if there was actual rotation at the cloud base. One could argue that there is some rotation, but before and after the dust-up it just looks like developing scud, so it may just be a slight illusion.

I'm interested to see how the NWS Omaha rules on this new video (they were sent it and are looking into it as of yesterday).

 

[T Farncombe]

While I could certainly believe the third dust-up is a tornado, I'm not 100% convinced. Would have been nice to have a steadier+longer shot of it to see if there was actual rotation at the cloud base. One could argue that there is some rotation, but before and after the dust-up it just looks like developing scud, so it may just be a slight illusion.

For what it's worth I would agree with Mark on this one. IMO (respectfully and without seeing Dan Melby's vid), I think the screen cap may be deceiving. Tornado #2 in the screen cap posted by Rob H was a large multi vortex at this stage. I believe what is labelled as #1 may just be ragged base (further back) and the apparent dust whirl below is actually a suction vortex belonging to and being drawn into #2.

Mark, in your previous post (18 in this thread), you discuss another photo and question its claim to show three tornadoes.. Again - respectfully and for what it's worth - I don't think that it does. This looks to me to have been taken toward the end of the Pilger and east-of-Pilger tornadoes' life cycles. At the moment of this pic, IMO, the original Pilger tornado (left) took on a brief multiple vortex structure with two distinct funnels, while the east-of-Pilger tornado (right) continued as a strong/fat stovepipe. I believe there were two tornadoes on the ground that may have had the appearance of three. Here is a vid of mine that illustrates what I'm talking about; I suspect that the pic from post 18 was taken at around the same time but from closer, further to my northwest.

https://www.youtube.com/watch?v=es4LcyAbRsI&feature=youtu.be

Travis

 

[Charles Kuster]

Thanks. I am interested in understanding HOW they could share an RFD; since the RFD is part of the overall mesocyclonic circulation and required for both tornadogenesis and tornado sustenance, how could each tornado NOT have its own RFD?

There are a lot of interesting and good questions about this supercell posted, but many of them are challenging to answer due to the poor spatial and temporal resolution radar data available. From what I have looked at, it looks like the tornadoes occurred with separate mesocyclones and therefore had separate RFDs. Looking at the first radar image below (from 2116 UTC), there is not a continuous area of inbound velocities behind each of the mesocyclones. Instead, there is a weakness (weak inbound velocities near 0 m/s) in between the two circulations suggesting that there are two separate circulations (mesocyclones). Winds would be more perpendicular to the radar beam on the north and south side of the separate mesocyclones, so the radar "sees" this as near zero velocities. The second radar image is from earlier (2108 UTC) at the 6.40 degree elevation angle which is looking much higher (11 km) in the storm. This image shows that there are three separate mesocyclones high in the the supercell, one of which being the dissipating Stanton mesocyclone (#1). I also think this is supported by some of the video I have looked at (particularly this one: https://www.youtube.com/watch?v=ii9QCTkmmpQ) that shows the RFD wrapping around the first Pilger tornado and the second tornado developing under what appears to be a new mesocyclone.

Radar base velocity image from 2116 UTC.

6.40 degree (11 km) velocity at 2108 UTC. Mesocyclones indicated by numbers, with the Stanton mesocyclone as #1, "Pilger 1" as #2 and "Pilger 2" as #3.

I also agree with Bob about the feature at 4:19 pm CDT (2119) not being a tornado based on videos and radar imagery. It is hard to tell exactly where that feature is relative to "Pilger 1" but radar imagery from 2121 shows only weak rotation (probably associated with the overall mesocyclone) just to the WNW of "Pilger 1" and convergence just to SW, indicating that this might be an area of updraft (wall cloud). The rotation does get stronger on radar by 2132 UTC, but it has no vertical continuity, so it is either a rather shallow vortex or an artifact.

Base velocity from 2121 UTC.

Base velocity from 2132 UTC.

Bram's radar loop and this one I created (https://www.youtube.com/watch?v=aItKahqwqe4&list=UUeHvBfIv6sy6IhHrDb5R94w) should allow for a more "fluid" depiction of the radar imagery beyond the individual images posted above for those interested. This was definitely an interesting case and it would have been amazing to have mobile radar data or phased-array radar data for this storm!

 

[Bob Schafer]

Has anyone seen any vid of these tornadoes from anyone who was coming up 15 from the south? I haven't, but I've been insanely busy, too. I know there were other chasers on that road with me. I'll be getting my vid posted on YT within a few weeks (long story), for anyone interested, and I'll post on ST when that happens.

 

[Jamey Ahlgrim]

I just posted these links in the reports thread but I have relinked them here. This is my video from 5 miles south of Pilger on Highway 15 looking north. The first link is real time and the second link is a time lapse of the same video. You can see both tornadoes form and mature in this video. Hopefully this video can shed some light on some of the questions in this thread. However, for me, these videos leave me with more questions than answers lol.

My GPS location from Spotter Network for this video is 41.9314 -97.0598

20 minute video of Pilger tornadoes

8x Time Lapse of video above

 

[John Bowles]

The Basehunters video is pretty amazing, especially when one of the tornadoes crosses the road right in front of them with the other tornado photogenically in the background! One thing about that sequence is troubling. There is another vehicle that is tagging alongside them, and it's hard to tell if it is part of their convoy or not. Anyway as they approach the tornado the other vehicle gets even closer, almost touching the debris cloud before the tornado leaves the road. While fascinating to watch, I hope this wasn't some macho game to see how close each vehicle dared to get.

I've seen a lot of posts about the white car. I think its worthwhile to point out that if a car 50 ft in front of you is "too close", than so are you. Basehunters shouldn't be given a pat on the back while everyone chastises the white car. They were in little more danger than Basehunters themselves were. At one point in the video, before the white car even shows up, stuff is flying in between their car and the next road sign.

 

[Dan Melby]

I think it is funny how there has been quite the debate on if there were three tornadoes or not. I frequent this site from time to time so I though that I would come on and see some photos and I cam across this discussion. I really don't care who says it is not a tornado(NWS included). Having witnessed it first hand, I know what I saw and frankly I think the proof is pretty compelling. Though only brief, there were 3 tornadoes @ 4:17pm.

 

[Mark Ellinwood]

I think it is funny how there has been quite the debate on if there were three tornadoes or not. I frequent this site from time to time so I though that I would come on and see some photos and I cam across this discussion. I really don't care who says it is not a tornado(NWS included). Having witnessed it first hand, I know what I saw and frankly I think the proof is pretty compelling. Though only brief, there were 3 tornadoes @ 4:17pm.

Your clip is fairly compelling evidence, but take a look at it from those watching the video. The shot is *extremely* shaky and brief, and it's hard to discern any rotation (at least any that might not be an illusion of the updraft) in the cloud base above the dust-up from the supposed third tornado. It very well could have been a third tornado, but with the evidence at hand it's hard to say with absolute certainty that it was.

Also, considering how extremely rare it would be to have three completely separate tornadoes at once, it's no surprise that any and all evidence is brought into question and highly scrutinized. It's just part of science... always be skeptical and question everything.

 

[Dan Melby]

Bob that was my video posted earlier in this thread. Not sure if you were being sarcastic in your first statement above.

Mark I am not trying to make you a believer. I know what I saw and I am sticking to it. You are entitled to your own opinion.

 

[rdale]

Here's great video found by Tim Marshall from a front-porch watcher (you know it's not a chaser because there's no yelling, jumping up-n-down, profanity, selfie shots, or driving into the rain bands.)

https://www.youtube.com/watch?v=KyF_pYYe4QQ

 

[Marcus Diaz]

Yeah, some random farmer got the best footage of that day. Pretty funny how that works.

 

[David Williams]

No kidding Marcus! There has been a lot of amazing footage of these twin (although, now I think triplets is the more appropriate term tornadoes. But that footage was the best. Those horizontal vortices at the beginning are amazing. Thanks rdale for posting it and thanks to Tim for hunting it down.

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