Funnel or Scud?

[Jim Hunt]

So today seemed like a nothing day for severe weather. I came in from walking the dog, the wife was at a club meeting,, and I decided to get on 6 meters and see if the band was open.

I flipped on the rig and it was on the local repeater and I hear a few guys talking about law enforcement reporting a funnel/touchdown in a bean field. I glance at radar and see nothing. Anyway, I jump in the truck and head out....

I didn't see anything but one fellow snapped off this photo. This was on the back side of a moderate rain cell. The NWS said it was nothing over the phone when someone called it in. Radar didn't support anything severe.

So do we have a funnel, a scud, or are we just plain nuts?

 

[rdale]

As we say every time one of these is posted - without video showing rotation, you can't tell. You can guess, or run an extensive poll, or flip a coin. Without video - no answer matters.

 

[Laura Duchesne]

I'll crack at it.... a shear funnel? Happens in scud environments sometimes... not tornadic.

 

[Gene Moore]

I voted funnel cloud, reasons....
It appears laminar not ragged like the scud
It's coming from a lowering
I saved it in my system, brought it up in Photoshop, applied darkness, contrast and unsharp mask and it looks solid and extends close to ground.

If it's not, I'm certainly fooled. Also, you don't need a thunderstorm to get a funnel cloud, just low level shear. I saw one this spring over saturated ground with fog (LCL near ground) and it was turning very slowly.

Gene Moore

 

[Brian Stertz]

Yep I'm on board with Laura on that line of thought....shear funnel in a very moist environment. Too developed to be a scud tag, and it appears to be attached.

 

[Brandon Sullivan]

I voted scud, as it appears the storm is very ill defined. And it doesnt appear to be a significant lowering, plus you can see the right side of the lowering is transparent, which indicates lack of upward motion, and not a typical wall cloud/lowering. As rdale said, we cant really tell without motion.. It is attached to a cloud base, and looks nice. But I went with scud on this one. And I dont think your crazy.

 

[Angie Norris]

Count me in on the shear funnel...good environment for shear funnels, definitely attached to the cloud base, too developed to be scud.

 

[scott r currens]

You have a photograph that clearly shows laminar funnel extending from a lowered cloud base 2/3 of the way to the ground and a report of a touchdown from a credible source. That is all I need to reasonably conclude that this was a tornado. My guess is that this funnel was associated with a mini or low-topped supercell. That is probably why it didn’t look like much on radar. I’ll have look into the environment that produced this storm.

 

[Marko Korosec]

Looks like cold-air funnel to me. I saw very similar feature this spring here.

 

[rdale]

Temps were in the 80's yesterday - not quite cold air conditions.

And Scott - he didn't indicate that a spotter saw it touch down, just a police report. This is not from a low-topped or mini- or super-mini supercell. Take a look at radar and conditions over Indiana at the time and it won't take very long to reach that conclusion.

 

[Jim Hunt]

Temps were in the 80's yesterday - not quite cold air conditions.

And Scott - he didn't indicate that a spotter saw it touch down, just a police report. This is not from a low-topped or mini- or super-mini supercell. Take a look at radar and conditions over Indiana at the time and it won't take very long to reach that conclusion.

Not that I will convince you it is a funnel *wink* but the temps were at 70-71 and falling.

 

[rdale]

Still not cold-air funnel conditions ;>

 

[Van DeWald]

Well, cold core funnels are associated with cold air aloft, not necessarily cold conditions at the surface. But, in looking at the mesoanalysis for this time, the cold core (if you could call it that) was across northern Indiana, not central Indiana. There was an axis of surface vorticity nearby, and 0-3km CAPE approaching 100 J/kg. These are two things that can contribute to weak funnels in the presence of convection, but the low level lapse rates were quite meager aound 5.5 to 6.0 degrees. LCL heights were quite low though, around 750 meters, which would be very favorable for funnels, with 77 over 67 at KIND at 23z. Thus, I don't think it's a true cold core funnel, but it sure does look like a weak funnel, and given several supportive ingredients (surface vorticity, 0-3km cape and low LCL), I voted funnel, but as Rob stated, can't tell for sure unless you see more pictures or video. I didn't look at any radar data either, just some archived SPC mesoanalysis.

 

[Dave Kaplow]

We've all (or most of us have, anyway) seen funnels that form in obviously non-tornadic conditions. Weak/transient shear funnels can appear out of virtually any convection. I wouldn't place too much faith in the radar, you simply can't rule out a shear funnel/landspout by looking at radar. Here we have what looks like a well-formed funnel coming out of a convective updraft base. Who is to say that local conditions couldn't have created a shear funnel?

Without any further information, based on the picture alone, I'd say the key here would be persistence, or lack of it. Was this thing persistent? Or was it a momentary feature that soon morphed into something else? If its lifespan was measured in minutes rather than seconds, then my vote is definitely funnel. The odds of non-rotating scud taking on this kind of appearance and then staying that way are IMO rather low.

 

[Damon Poole]

Was there a debris cloud associated with this feature? I don't see one, or anything else indicating a touchdown. I think at most, you might, have a very weak funnel, if, you can show persistant rotation. Barring that, I have to vote scud on this one.