Severe WX February 16-17th, 2022 Severe Threat (2 Viewers)

Evan

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Yeah, this is bizarre. Debris doesn't hang in the air this densely packed, for this long from a tornado that has dissipated, but there's NOTHING there on velocity.

Definitely weird. It finally dissipated. I think on higher tilts and from other radars there did still appear to be a bit of rotation even after it was gone from 0.5 KBMX.
 

Evan

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Interesting storms forming in NW Alabama.
 

Tennie

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A good chunk of northern Alabama is now under flash flood warnings. To anyone in/near those affected areas, PLEASE take your flash flood precautions tonight!
 

Richardjacks

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Definitely weird. It finally dissipated. I think on higher tilts and from other radars there did still appear to be a bit of rotation even after it was gone from 0.5 KBMX.
That whole thing was just weird with the cc and velocity couplet or lack thereof ...haven't seen that before
 

AL_ham_op

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Can someone explain the debris signatures on that Leeds storm? How do you have that kind of debris showing up on radar but no real reports of damage? I was really expecting major damage at least over a small area with that.

Is it just leaves being lofted up? Just how much debris does it take and how large does it have to be to show up as a debris signature?
 

buckeye05

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Can someone explain the debris signatures on that Leeds storm? How do you have that kind of debris showing up on radar but no real reports of damage? I was really expecting major damage at least over a small area with that.

Is it just leaves being lofted up? Just how much debris does it take and how large does it have to be to show up as a debris signature?
Essentially any tornado can produce a TDS, even EF0s. Also yes, something as small and light as leaves or roof shingles can cause a TDS to pop up. With that said, for reasons that I’m not clear on, not all tornadoes produce TDSs, even strong ones. A good example would be the EF3 tornado that struck Elon, VA on April 15, 2018. The community took a direct hit, and multiple homes were completely destroyed, yet I remember that no TDS appeared when it moved through Elon. Weird stuff.
 

Equus

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Well, like 3/17 and 3/25 we got an event that played out about as expected but much further east than expected; Mississippi still resting from the ridiculous thrashing it got in April 2020 I guess. Warm sector supercells developed but later and further east than many had planned on, though some models seemed pretty close on it. Models were also closer than I thought on thermos - I expected 65°+ dews to advect further north than models thought given the very usual underestimating of those values. The fairly meager instability didn't help things get going over MS and the poor lapse rates esp in the mid-levels didn't do a lot for the towers that tried to grow in those confluence band showers over S MS. We definitely got a bit of a thrashing in AL though a bit later and further east than most expected - but at this point it's becoming almost a routine lol. What's less than routine is the insane helicity RAP was picking up as the storms started going nuts in AL; widespread 600-800+ 0-3km SRH is wild for a warm sector! No doubt that little overlap of highest shear and furthest north 500+ CAPE helped kick the already established line segments into gear (and into supercell structures, with slightly backed surface winds)
 

maroonedinhsv

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Essentially any tornado can produce a TDS, even EF0s. Also yes, something as small and light as leaves or roof shingles can cause a TDS to pop up. With that said, for reasons that I’m not clear on, not all tornadoes produce TDSs, even strong ones. A good example would be the EF3 tornado that struck Elon, VA on April 15, 2018. The community took a direct hit, and multiple homes were completely destroyed, yet I remember that no TDS appeared when it moved through Elon. Weird stuff.
Without researching it, my initial thought is that distance from the radar is one key aspect. The greater the distance between the storm and the radar, the higher the beam - I would imagine that as the beam height increases, the likelihood of seeing debris decreases.
 
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Without researching it, my initial thought is that distance from the radar is one key aspect. The greater the distance between the storm and the radar, the higher the beam - I would imagine that as the beam height increases, the likelihood of seeing debris decreases.

This tornado was pretty close to the BMX radar, though. I think the 0.5-degree tilt was hitting it at less than 2kft.
 

maroonedinhsv

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This tornado was pretty close to the BMX radar, though. I think the 0.5-degree tilt was hitting it at less than 2kft.
Right, so that's the opposite effect - the lower the beam, the more "debris" that will show up even if it's not real. If the beam is low enough, I would think you could see the dust cloud from a storm moving across a recently plowed field. Again, this isn't a research-backed statement - just my hunch.
 

Equus

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Actually very much on the subject in the 4/5 thread about preliminary ratings sometimes being changed before Storm Data, very unexpected update from BMX tonight on the Boley Springs tornado from 2/17 based on tree damage - upgraded from EF0 to very high end EF1. Big kudos to BMX for immense attention to detail and going the extra mile to ensure accurate ratings when new info comes in; they're in the middle of surveying 9 tornadoes from 4/5 and 12 from 3/30 but still put up an update for this minor tornado two months ago.

202204090127_PNSBMX.png
 

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