Beaver Tail?

[Drew.Gardonia]

I was on a storm in Memphis on Wednesday and radar indicated a large tornado moving towards the city (I was being directed by Jeremy Holmes and Jeff Piotrowski over the phone).

Anyhow, as i get into the city I see what appears to be a funnel hanging at a strange angle, more horizontal, but as I get closer it starts to upright itself.

The NWS in Memphis is calling it a "Beaver Tail".

http://www.commercialappeal.com/news/2011/may/25/ominous-clouds-over-memphis-no-reports-severe-weat/

I don't care what they say, that thing was rotating, not violently or really fast, but it was rotating and it was defined and I'm hoping the video I was able to recover will show that.

Long story short, I was videoing on my 5d-MkII when it flased "Card Full" at me, and it didn't save any of the video (or so I thought). a friend recommended some software that recovers lost video and image files, and it worked, but I had to pay a company online to repair the corrupt video file, which I'm waiting for the video now.

here's some screenshots from the recovery preview of the video I was able to get. From my vantage point it looks like this thing would have had to have been on the ground, but no touchdowns were reported.

So is it a Funnel or Beaver Tail???

 

[rdale]

Looks like an SLC to me...

 

[Drew.Gardonia]

Looks like an SLC to me...

what's an SLC? sorry but not everyone knows the abbreviated terms for everything, so please don't use abbreviations and assume that everyone will know what you're talking about.

 

[David Wolfson]

Assuming the storm is moving from right to left, the broad roll at cloud base and the direction of the rain foot suggest to me that the feature defines a tongue of moister air drawn up over the ambient into a more vigorous portion of the updraft ahead of the storm. Broadly speaking, a SLSC -- Scary Looking Shelf Cloud. FWIW, IMO.

 

[Drew.Gardonia]

Assuming the storm is moving from right to left, the broad roll at cloud base and the direction of the rain foot suggest to me that the feature defines a tongue of moister air drawn up over the ambient into a more vigorous portion of the updraft ahead of the storm. Broadly speaking, a SLSC -- Scary Looking Shelf Cloud. FWIW, IMO.

actually I was driving west towards memhpis so it was moving from left to right

 

[David Wolfson]

Ok, I guess that makes it, technically, a SLBTC (Scary Looking Beaver Tail Cloud) like the NWS mets said....

 

[Jason Foster]

Not a beaver's tail. Kinda surprised the NWS met would call it that. If you have video...that's always plus...but looks to me like you captured A good strong stream of cool air getting sucked up into a non-rotating updraft. Beaver tails are associated with rotating wall clouds in well formed supercells and tend to be more horizontal along the ground. Similar in that they both suck in cool air, but in the beaver's case...it feeds the wall cloud, I believe helping to induced some of that rotation (but I'd have to dbl check that part).

SLC is pretty much it...but still a good capture. The bottom picture might even qualify as a "scud bomb" when the scud pretty much connects to the ground. That's assuming there was no rotation (and by the position on the cloud base above...I'd say no). Video would be great though.

 

[rdale]

I like this description

http://www.youtube.com/watch?v=h-fdT8kmDmk

 

[Jeff Duda]

It's just an inflow tail...

"Show's over people! Nothing to see here."

 

[Jason Boggs]

Not a beaver's tail. Kinda surprised the NWS met would call it that. If you have video...that's always plus...but looks to me like you Beaver tails are associated with rotating wall clouds in well formed supercells and tend to be more horizontal along the ground. Similar in that they both suck in cool air, but in the beaver's case...it feeds the wall cloud, I believe helping to induced some of that rotation (but I'd have to dbl check that part).

I have to disagree. Beaver tails are not associated with wall clouds. Beaver tails can occur when wall clouds are present, but sometimes they don't. Beaver tails are moisture drawn into the updraft of the storm. I think you're referring to a tail cloud. A tail cloud is a feature of a wall cloud, but beaver tail's are not.

 

[Skip Talbot]

Its not a funnel. Beaver tail is a much closer description to what the feature is although a classic beaver tail is flatter and more pancake shaped usually connected to a large wall cloud or meso. What it appears to be is a rain cooled, inflow based lowering. Inflow tails, beaver tails, and wall clouds are formed by similar mechanisms. I'm surprised no one has suggested wall cloud. Its not a classic, bell shaped wall cloud and is smaller and more tail than it is body, but its the same process at work here. The storm's inflow is pulling in the rain cooled air from the precip core off to the right and its condensing under the updraft base. Remember, if the feature points toward the rain its a wall cloud. If it points away, its a shelf cloud. You'd look for rotation more on the left side of that feature than you would at the tip. I'd expect that lowering to bulk up a bit more before an attempt at tornadogenesis is made, with more of a lower, flatter base and an RFD clear slot, but otherwise I'd say you've got a half assed attempt at a wall cloud here. Yes, its a very dramatic and photogenic feature. However, the right side more than likely is not rotating much if it at all, is not a funnel, and is probably not close to producing a tornado. There are always exceptions, but generally speaking most similar appearing features I have seen do not immediately produce looking like this.

 

[Chad Ringley]

Actually saw this exact feature on one of the Memphis TV station footage that was streaming. Also agree that it was formed by the inflow pulling in rain cooled air.... It wasn't rotating and there wasn't a whole lot of cloud-based rotation anywhere at the time.

 

[Danny Neal]

Agreed. I saw it live and was sure someone was going to mistake it as a funnel cloud. They even did a close up on it. There was a lot of rising and 'rolling' motions, but beyond that there wasn't really anything to write home about. I wasn't surprised to see amateur reports of a tornado going through mid-town Memphis though. There was no doubt in my mind someone was going to report a tornado on that feature.

 

[Danny Neal]

A beaver tail basically is a demarcation in the storm.... it forms because it is where the cool outflow and warm inflow are met. They are not connected to a wall cloud but are often found in the updraft region of a supercell extending out toward the NE. From my blog:

The long laminar looking cloud extending to the right or north. This is known as a beaver tail. It forms along the boundary created by the forward-flank downdraft. The area of precipitation is cool while the area you are viewing the storm from is warm and moist. The beaver tail will form where the two meet and mark it out by a long line of clouds shaped like a beavers tail

 

[Jason Foster]

I have to disagree. Beaver tails are not associated with wall clouds. Beaver tails can occur when wall clouds are present, but sometimes they don't. Beaver tails are moisture drawn into the updraft of the storm. I think you're referring to a tail cloud. A tail cloud is a feature of a wall cloud, but beaver tail's are not.

OK...I could be wrong. I thought they were the same (Beaver's Tail VS. Tail Cloud)...maybe I've been calling them the wrong thing all these years. The picture submitted in the other post does to me look like the Beaver's tail I was referring. I have to go back and check my Skywarn or NWS Material to see if I got it wrong...or am speaking wrong.

Add:
The other feature that comes to mind is the "inflow band" as I've said for years...but they are distinctly different than the beaver's tail (well not that they both are inflowing winds) and I don't associate with the wall cloud. Again...I'm gonna grab a book and double check myself.